Create NewFamily block
Change attributes to have a multiple categories instead of one free-text category
Temp stage of attribute/category changes
Merge branch 'origin/develop'

Conflicts:
	Rock/Rock.csproj
More changes to support adding categories to attributes
Add block for editing attribute categories (since they can't be added using the current category picker)
Merge branch 'feature-dt-attributecategory'
Update code generation to not ignore properties that were virtual because the belonged to an interface