Change IDimmableBlock to be ISecondaryBlock with a SetVisible() method instead
Rename IDimmableBlock to ISecondaryBlock
Update validation group names on GroupTypeDetail
Update GroupTypeRole migration to update the EntityType table with the new name so that role attributes still work
Update AttributeEditor and Validation Group handling, and all uses of such
Merge branch 'origin/develop'

Conflicts:
	Rock/Web/UI/Controls/Pickers/ItemPicker.cs
Removed check for VS 2012 to disable HttpInternals (I had no "VisualStudioEdition" environment variable).