Add support for simple id associations, non-MongoId ids, and multiple documents to ModelFilter; copy changes to FormContractor and DatagridBuilder from SonataDoctrineORMAdminBundle
fixes dotted property path references to associations plus more consistency with DoctrineORMAdminBundle.
Merge pull request #30 from SweepingDesign/sdmaster

Sdmaster
Merge pull request #32 from jvandesande/relation-list

Show relation in list view even if no admin association is set (fixes #31)