Revert "ARel only requires the connection from the AR class. Simply return the AR class rather than jump through hoops and store ivars"

This reverts commit d65e3b48.

ARel only requires the connection from the AR class. Simply return the AR class rather than jump through hoops and store ivars

Make serialized columns with explicit object_type return a new instance of the object instead of nil

Signed-off-by: NSantiago Pastorino <santiago@wyeworks.com>

Signed-off-by: NSantiago Pastorino <santiago@wyeworks.com>

Specify the STI type condition using SQL IN rather than a whole load of ORs. Required a fix to ActiveRecord::Relation#merge for properly merging create_with_value. This also fixes a situation where the type condition was appearing twice in the resultant SQL query.

After 304d38c0 we don't need the
new_record? check anymore.

Added ActiveRecord::Base#has_secure_password (via ActiveModel::SecurePassword) to encapsulate dead-simple password usage with SHA2 encryption and salting

* rename method names (actually in tests)
* rename instance variable @_named_scopes_cache to @_scopes_cache
* rename references in doc comments
* don't touch CHANGELOG :)