public / sequelize

This commit adds the ability of hooks for the DAOFactory. The following
hooks (in their order of operations) are:

(1) beforeValidate(dao, fn)

(-) validate

(2) afterValidate(dao, fn)

(3) beforeBulkCreate(daos, fields, fn)
    beforeBulkDestroy(daos, fields, fn)
    beforeBulkUpdate(daos, fields, fn)

(4) beforeCreate(dao, fn)
    beforeDestroy(dao, fn)
    beforeUpdate(dao, fn)

(-) create / destroy / update

(5) afterCreate(dao, fn)
    aftreDestroy(dao, fn)
    afterUpdate(dao, fn)

(6) afterBulkCreate(daos, fields, fn)
    afterBulkDestory(daos, fields, fn)
    afterBulkUpdate(daos, fields, fn)

There's a new file called hooks.js which works very similar to
mixins.js which just extends a prototype.

You can add the hooks like so...

... via .define():

var User = sequelize.define('User', {
  username: DataTypes.STRING,
  mood: {
    type: DataTypes.ENUM,
    values: ['happy', 'sad', 'neutral']
  }
}, {
  hooks: {
    beforeValidate: function(user, fn) {
      user.mood = 'happy'
      fn(null, user)
    },
    afterValidate: function(user, fn) {
      user.username = 'Toni'
      fn(null, user)
    }
  }
})

... via .hook() method

var User = sequelize.define('User', {
  username: DataTypes.STRING,
  mood: {
    type: DataTypes.ENUM,
    values: ['happy', 'sad', 'neutral']
  }
})

User.hook('beforeValidate', function(user, fn) {
  user.mood = 'happy'
  fn(null, user)
})

User.hook('afterValidate', function(user, fn) {
  user.username = 'Toni'
  fn(null, user)
})

... via direct method:

var User = sequelize.define('User', {
  username: DataTypes.STRING,
  mood: {
    type: DataTypes.ENUM,
    values: ['happy', 'sad', 'neutral']
  }
})

User.beforeValidate(function(user, fn) {
  user.mood = 'happy'
  fn(null, user)
})

User.afterValidate(function(user, fn) {
  user.username = 'Toni'
  fn(null, user)
})

Quick example:

User.beforeCreate(function(user, fn) {
  if (user.accessLevel > 10 && user.username !== "Boss") {
    return fn("You can't grant this user that level!")
  }

  return fn()
})

User.create({
  username: 'Not a Boss',
  accessLevel: 20
}).error(function(err) {
  console.log(err) // You can't grant this user that level!
})

As of right now, each hook will process in the order they where
implemented / added to the factory.

To invoke the hooks simply run...

Model.runHooks.call(Model.options.hooks.<hook>, <args>, <callback>)

Some model hooks have two or three paramters sent to each hook
depending on it's type.

Model.beforeBulkCreate(function(records, fields, fn) {
  // records = the first argument sent to .bulkCreate
  // fields = the second argument sent to .bulkCreate
})

Model.bulkCreate([
  {username: 'Toni'}, // part of records argument
  {username: 'Tobi'} // part of records argument
], ['username'] /* part of fields argument */)

Model.beforeBulkUpdate(function(attributes, where, fn) {
  // attributes = first argument sent to Model.update
  // where = second argument sent to Model.update
})

Model.update(
  {gender: 'Male'} /*attribures argument*/,
  {username: 'Tom'} /*where argument*/
)

Model.beforeBulkDestroy(function(whereClause, fn) {
  // whereClause = first argument sent to Model.destroy
})

Model.destroy({username: 'Tom'} /*whereClause argument*/)

For 1.7.x backwards compatibility, I've added a new method called
.hookValidate() since .validate() is a synchronous function. All of
Sequelize's API functions will invoke .hookValidate(), but if you
utilize the .validate() function outside of Sequelize then you'll
need to update your code if you want to run before/afterValidate hooks.

Sequelzie 2.0.x will not need this change simply because it's
.validate() method is already asynchronous. However, it will have the
.hookValdate() function in order to make the transition from 1.7 to 2.0
smoother and easier. Eventually we'll want to deprecate this function.

In addition to this commit, I've also completed the following tasks:

Move validation of enum attribute value to validate method

I had to complete that task in order to get the validate hooks
working properly.

And the last thing, I fixed executables.test.js if your DB didn't use
the default values for config/config.js, this was causing errors for me
on my local machine.

Properly copy the options objects passed to find and findall

Fixes a bug with .destroy() on a DAO record

This only affected Postgres really, but when you did .find(), etc. and then
.destroy() on the actual DAO rather than the DAOFactory, sometimes the
QueryGenerator.deleteQuery() would have trouble finding the primary keys for
that table. This provides additional info to Postgres' deleteQuery() function
just in case.

This commit adds a fourth argument to Postgres' QueryGenerator.deleteQuery() for
declaring a DAOFactory.

Fixes Postgres' ability to search within functions.

This is a pure and simple fix for searching with a Postgres' array column type.
This commit changes hashToWhereConditions by adding a second argument of sending
the factory's details over and checking for column type if the hash/value/first
argument is an array. For the actual search we just utilize a simple overlap &&
boolean search.

Add Sequelize#model to fetch DAOFactory of previously defined model

ENUM types will no longer break in Postgres

Fix: Postgres connection issues

Plus cleaning up many-many join to be more understandable

Default was integer, which led to casting errors returning the incorrect data

…t when declaring tableName.

Postgres will now add enum's values on .sync() if you were to add
entires into the attribute's.value. It'll also add the enum type in
the proper order. For example:

```js
Table = sequelize.define...
  mood: {
    type: DataTypes.ENUM,
    values: ['happy', 'sad']
  }

// For some reason down the road you redefine the same table
// ...
  mood: {
    type: DataTypes.ENUM,
    values: ['neutral', 'happy', 'sad', 'joyful']
  }
```

Will result in the following SQL:

```sql
ALTER TYPE "...enumTypeName..." ADD VALUE 'neutral' BEFORE 'happy';
ALTER TYPE "...enumTypeName..." ADD VALUE 'jouful' AFTER 'sad';
```

- ```.drop()``` will now pass the options object through (optional)
- Added Postgres.QueryGenerator.pgListEnums(tableName=null,
   attrName=null, options) which lists all of the ENUM types for
   Postgres, if you don't specify an attribute and tablename then
   Sequelize will list all of the Enums
- Added Postgres.QueryGenerator.pgEnumAdd(tableName, attr, value,
   options) which will alter the enum type and add values
- Added Postgres.QueryGenerator.pgEnumDrop(tableName, attr) which
   will drop the enum type
- Postgres.QueryGenerator.pgEnum() will no longer try to drop the
   type unless {force: true} within the ```.sync()``` commands
- Refactored ```QueryInterface.createTable()``` in order to allow
   Postgres to create enum types explicitly rather than from
   Postgres.```QueryGenerator.createTable()```
- Refactored QueryInterface.dropTable() -- same as ```createTable()```
   changes .. also {force: true/force} will now set options.cascade
- QueryInterface.dropAllTables() will now correctly add a quote
   identifier to table names for MySQL

Closes https://github.com/sequelize/sequelize/issues/546

Some users were experiencing problems with Postgres connections leaking when
they didn't enable pooling. This commit should fix the problem.

- In prototype.disconnect() we now properly call this.client.end with
  this.client.end.bind(this.client) (as shown in the node-postgres wiki).
- We no longer check for readyForQuery on this.client as that value may not
  always be populated by node-postgres (possibly a bug on node-postgres).

This should close https://github.com/sequelize/sequelize/issues/859

This commit fixes the following connection problems:
* Pools should now properly release themselves always
* You can now set a "TestOnBorrow"-like functionality with
  config.pool.reapInterval).
* Heroku should be able to properly send the correct DB credentials.

Allows us to define our own timestamp columns.