Remove webrtchelper and reorg svmp checkouts

* webrtchelper is obsolete now that fbstream and the input server are merged
* change protocol checkout location to external/svmp/svmp-protocol-def
* change input server checkout location to external/svmp/svmpd
* remove old commented out lines

Change-Id: I1fb1f4dc6b6dc67d3eae8073734552be1158e8ba