+ added memory layout tests for the small and medium memory models



git-svn-id: http://svn.freepascal.org/svn/fpc/trunk@28078 3ad0048d-3df7-0310-abae-a5850022a9f2
+ added a test for the tiny memory layout



git-svn-id: http://svn.freepascal.org/svn/fpc/trunk@28079 3ad0048d-3df7-0310-abae-a5850022a9f2