Fix issue #39 : Allows internal filters to be loaded in .GRF files by additionally register internal filters from MTA thread that never exits. 
Ideally need to call CoRevokeClassObject on exit but it may not be a problem for in-proc objects.

git-svn-id: http://graph-studio-next.googlecode.com/svn/trunk@154 c2f33eb2-41b2-391d-4cb4-d9d0608729ba