Add go wrapper, streamline java decoder: (#524)

* add (c)brotli golang wrapper
 * remove (language-specific) enums in java decoder
diff --git a/BUILD b/BUILD
index 1dea6d8..bc86186 100644
--- a/BUILD
+++ b/BUILD
@@ -100,3 +100,7 @@
         ":brotlienc",
     ],
 )
+
+load("@io_bazel_rules_go//go:def.bzl", "go_prefix")
+
+go_prefix("github.com/google/brotli")