Data Access class can specify the default 'key' field name.

For example, it the db-class value is FileMaker_FX, the 'key' value in
context can be omitted, and 'key' is automatically supplied as "-recid"
by IM.
Merge branch 'support-filemaker-portal-access' of https://github.com/msyk/INTER-Mediator into support-filemaker-portal-access

Conflicts:
	develop-im/Sample_form/include_FMS2.php
Conflict resolve for include_FMS2.php