Add basic function and trigger migrations

Added the ability to define migrations that create, drop, and rename
both functions and triggers (since triggers need functions).  This
allows migrations to handle more of the requirements of setting up
the underlying SQL database behavior.

This version currently only provides support on postgresql.
Merge remote-tracking branch 'upstream/master' into basic_function_and_trigger_migrations
Initial commit for join table model
Add Sequelize#model to fetch DAOFactory of previously defined model
Merge pull request #868 from jwilm/model-accessor

Add Sequelize#model to fetch DAOFactory of previously defined model
Sequelize#model
v1.7.0-beta.0
insert into join table
Initial commit for join table model
insert into join table
Merge head
Support for getting join table model data
alias the queryinterface on hasmany double linked for brevity
Create an alias for connectorDAO for brevity
slight variable renaming
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.
Merge pull request #879 from durango/anyarray

Fixes Postgres' ability to search within functions.
Updated changelog
Make the ordering / quoting API consitent
Moved querygenerator into the abstract folder