Update CS:GO, Dota2, Steamclient (beta 1379375636) protobufs and Steamclient EMsgs
Merge remote-tracking branch 'origin/steamclient-beta'
Update Dota 2 and Dota 2 Text protobufs.
Updated Dota 2 protobuf generation script for gcmessages split.
Regenerated Dota 2 protobufs.