CBLT-198:  install sync_gateway version {SYNCGATE_VERSION}

Although there is a param for each platform in the upstream job
"build_sync_gateway_master__POST" that job is hard-coded to use
the ubuntu-x64 param only.  Will need to expand this once there
is more than one platform on which we build android.

Change-Id: I3893ac87979a852f806e6ad983289f89d0781c09
Reviewed-on: http://review.couchbase.org/34187
Reviewed-by: Philip Labee <philip@couchbase.com>
Tested-by: Philip Labee <philip@couchbase.com>