Update instances.md

Changed method `instance.updateAtttributes()` to `instance.update`, according to latest API to avoid confusion:
https://github.com/sequelize/sequelize/blob/f678009d7514b81a6f87e12b86360e9a597e3ca8/lib/instance.js#L765

docs/docs/instances.md

@@ -84,12 +84,12 @@ task.title = 'a very different title now'
 task.save().then(function() {})
 task.save().then(function() {})
  
  
 // way 2
 // way 2
-task.updateAttributes({
+task.update({
   title: 'a very different title now'
   title: 'a very different title now'
 }).then(function() {})
 }).then(function() {})
 ```
 ```
 
 
-It's also possible to define which attributes should be saved when calling `save`, by passing an array of column names. This is useful when you set attributes based on a previously defined object. E.g. if you get the values of an object via a form of a web app. Furthermore this is used internally for `updateAttributes`. This is how it looks like:
+It's also possible to define which attributes should be saved when calling `save`, by passing an array of column names. This is useful when you set attributes based on a previously defined object. E.g. if you get the values of an object via a form of a web app. Furthermore this is used internally for `update`. This is how it looks like:
 
 
 ```js
 ```js
 task.title = 'foooo'
 task.title = 'foooo'
@@ -98,8 +98,8 @@ task.save({fields: ['title']}).then(function() {
  // title will now be 'foooo' but description is the very same as before
  // title will now be 'foooo' but description is the very same as before
 })
 })
  
  
-// The equivalent call using updateAttributes looks like this:
-task.updateAttributes({ title: 'foooo', description: 'baaaaaar'}, {fields: ['title']}).then(function() {
+// The equivalent call using update looks like this:
+task.update({ title: 'foooo', description: 'baaaaaar'}, {fields: ['title']}).then(function() {
  // title will now be 'foooo' but description is the very same as before
  // title will now be 'foooo' but description is the very same as before
 })
 })
 ```
 ```