Update transaction lock docs for version 3.0

lib/transaction.js

@@ -53,24 +53,27 @@ Transaction.ISOLATION_LEVELS = {
  *
  * ```js
  * t1 // is a transaction
+ * t1.LOCK.UPDATE,
+ * t1.LOCK.SHARE,
+ * t1.LOCK.KEY_SHARE, // Postgres 9.3+ only
+ * t1.LOCK.NO_KEY_UPDATE // Postgres 9.3+ only
+ * ```
+ * 
+ * Usage:
+ * ```js
+ * t1 // is a transaction
  * Model.findAll({
- *   where: ...
- * }, {
+ *   where: ...,
  *   transaction: t1,
- *   lock: t1.LOCK.UPDATE,
- *   lock: t1.LOCK.SHARE,
- *   lock: t1.LOCK.KEY_SHARE, // Postgres 9.3+ only
- *   lock: t1.LOCK.NO_KEY_UPDATE // Postgres 9.3+ only
+ *   lock: t1.LOCK...
  * });
  * ```
  * 
- * Postgres also supports specific locks while eager loading by using OF.
- * 
+ * Postgres also supports specific locks while eager loading by using OF:
  * ```js
  * UserModel.findAll({
  *   where: ...,
- *   include: [TaskModel, ...]
- * }, {
+ *   include: [TaskModel, ...],
  *   transaction: t1,
  *   lock: {
  *     level: t1.LOCK...,