Created LinkService and added unit tests.

Change-Id: I1f2104c873e5a9e2df34074d36cddc823e3b3ec5
diff --git a/lib/deps.json b/lib/deps.json
index 6ff4604..82992bd 100644
--- a/lib/deps.json
+++ b/lib/deps.json
@@ -70,7 +70,7 @@
       "netty-common"
     ],
     "GRPC_1.3": [
-      "grpc-core-1.3.0",
+//      "grpc-core-1.3.0",
       "grpc-protobuf-1.3.0",
       "grpc-stub-1.3.0",
       "grpc-netty-1.3.0",