Fixing DC-755 with tests

Corrects handling of MODEL_CLASS_PREFIX when migrating from YAML schema files so that the prefix is used for from and to models to correct behaviour where the whole database is dropped, and adding ticket tests
Adding tests for DC880 spurious migrations added when using behaviours
DC880 - Adding explicit tableName definition to versionable and searchable to prevent false migration generation

When using model prefixes and the searchable and versionable behaviours, migrations are built that drop and recreate indexes when nothing of the schema has changed. This commit fixes this by explicitly declaring a table name in these behaviours (based on the tablename of the owning class) so that the tablename for generated models is correct. Child classes can still override this value in their extended classes if required.
Case sensistivity issues with table name
Merge remote-tracking branch 'acoulton/DC-880' into D-880

Conflicts:
	lib/Doctrine/Migration/Diff.php