Repair clauselist comparison to account for clause ordering

Repair clauselist comparison to account for clause ordering

Fixed bug where the "simple many-to-one" condition that allows  lazy
loading to use get() from identity map would fail to be  invoked if the
primaryjoin of the relationship had multiple clauses separated by AND
which were not in the same order as that of the primary key columns
being compared in each clause. This ordering
difference occurs for a composite foreign key where the table-bound
columns on the referencing side were not in the same order in the .c
collection as the primary key columns on the referenced side....which
in turn occurs a lot if one is using declarative mixins and/or
declared_attr to set up columns.

Change-Id: I66cce74f614c04ed693dc0d58ac8c952b2f8ae54
Fixes: #3788