This prevent having to pass simple_col through multiple function calls
by defining whether or not references should be resolved with aliases
at the Query level.
Changed __eq__ to return NotImplemented instead of False if compared to
an object of the same type, as is recommended by the Python data model
reference. Now these models can be compared to ANY (or other objects
with __eq__ overwritten) without returning False automatically.
Hannes Ljungberg
Ian Foote
Simon Charette
ElizabethU
Mads Jensen