fixes to include-related bugs - 925 and 926

Fixes to bugs related to Include:
925 - Include doesn't work for entities with composite keys - when creating join predicates, we were using Expression.And operator, but expecting AndAlso later in the pipeline. Fix is to switch operators to AndAlso.

926 - Include doesn't work unless primary key on principal entity and foreign key on dependent entity are the same - we were creating invalid sql due to those two column names being switched. Fix is to switch them around to proper order.

@anpete @divega @ajcvickers 
No need to change naming here as these are nested private.