Make bazel build fully hermetic

We no longer reference @bazel_tools//third_party. All of our transitive
dependencies are now specified explicitly in our WORKSPACE file.

I also fixed the way that jar dependencies are exported, so we don't
break strict dependency checking.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=116421176

third_party/java/appengine_gcs_client/BUILD

@@ -4,8 +4,8 @@ licenses(["notice"])  # Apache License 2.0
 
 java_library(
     name = "appengine_gcs_client",
-    exports = [
-        "@appengine_gcs_client//jar",
+    exports = ["@appengine_gcs_client//jar"],
+    runtime_deps = [
         "@google_api_client_appengine//jar",
         "@google_api_services_storage//jar",
         "@google_http_client_appengine//jar",