java: Publish 2.1.6 to maven and bintray

Note: Needed a minor patch in x/ref to make this compile
-       v23_syncbase_Init()
+       v23_syncbase_Init(C.v23_syncbase_Bool(1))

in services/syncbase/bridge/cgo/jni.go

Changes covered:
- RPC can now switch endpoints automatically if a connection has been
  lost.
- Sync speed is vastly improved due to more frequent gen vector cuts.

Change-Id: Ia10cac1e967a3b32c8f2a576e8c6836b0f12ca82
2 files changed