Allow a SingleObjectSelector to be a stream::EDFilter

Backport of #3966 from @VinInn

Allow a SingleObjectSelector to be a stream::EDFilter
make VertexSelector a stream module

edm::EDFilter is pretty pervasive in CommonTools.
In my opinion it will be a hard task to migrate all those filters to be stream modules selectively...

just syntax, 
no regression expected
no regression observed