Add bazel rules that can be used by J2CL for building the jre.

Change-Id: Idedfdd70ca01aeb34bbb50447ede71b19c06b9a2
diff --git a/WORKSPACE b/WORKSPACE
new file mode 100644
index 0000000..d9c9105
--- /dev/null
+++ b/WORKSPACE
@@ -0,0 +1,2 @@
+# Bazel workspace file.
+workspace(name = "org_gwtproject_gwt")