MAGN-1002. Create Elements.OfFamilyType and Elements.OfCategory.
Merge branch 'master' of github.com:DynamoDS/Dynamo
Make AllElementsOf... nodes UI nodes so we can respond to doc changes.
Add migrations for OfType, OfCategory.
Move Revit selection tests to new project for Revit UI nodes. Add test stubs for Elements classes.
MAGN-2414. Remove catch in viz manager.
Merge branch 'master' of github.com:DynamoDS/Dynamo