Implement Bazel build

TEST PLAN:
  $ bazel test gitiles-servlet/...

Run debug version:
  $ sh {path/to/src}/tools/run_bazel_dev.sh

TODO:

 * publishing maven artifacts.
 * check out Bazel's generate_workspace.
 * intellij/eclipse project generation

Change-Id: I288011ce622536ce72c59a1961f962db9fe9e761

lib/soy/BUILD

diff --git a/lib/soy/BUILD b/lib/soy/BUILD
new file mode 100644
index 0000000..4f19143
--- /dev/null
+++ b/lib/soy/BUILD
@@ -0,0 +1,9 @@
+package(
+    default_visibility = ["//visibility:public"],
+)
+
+java_library(
+    name = "soy",
+    exports = ["@soy//jar"],
+    runtime_deps = ["@icu4j//jar"],
+)