Merge pull request #525 from robotboy655/master

Fixed duplicator crash
TTT: map-defined range for traitor button

Mappers can now set the range at which a traitor button is usable via
the new UsableRange keyvalue of ttt_traitor_button entities.
TTT: move base entities from DTVar to NetworkVar

Will happen for all entities at some point, but starting with base ents
here.
Merge remote-tracking branch 'upstream/master'