Add bazel rule to run buildifier; fix up formatting problems in bazel files

Change-Id: Ifa8ab12ed564fa2eaf5edd781281aa5cae52d17a
diff --git a/tools/build/bazel/bazel_version.bzl b/tools/build/bazel/bazel_version.bzl
index 4aa4b1c..cd175b0 100644
--- a/tools/build/bazel/bazel_version.bzl
+++ b/tools/build/bazel/bazel_version.bzl
@@ -15,12 +15,12 @@
 """
 
 def check_bazel_version():
-  if "bazel_version" not in dir(native):
-    fail("\nBazel version is too old; please use 0.15.* official release!\n\n")
-  elif not native.bazel_version:
-    print("\nBazel is not a release version; please use 0.15.* official release!\n\n")
-    return
+    if "bazel_version" not in dir(native):
+        fail("\nBazel version is too old; please use 0.15.* official release!\n\n")
+    elif not native.bazel_version:
+        print("\nBazel is not a release version; please use 0.15.* official release!\n\n")
+        return
 
-  if not native.bazel_version.startswith("0.15."):
-    fail("\nBazel version %s is not supported; please use 0.15.* official release!\n\n"
-            % native.bazel_version)
+    if not native.bazel_version.startswith("0.15."):
+        fail("\nBazel version %s is not supported; please use 0.15.* official release!\n\n" %
+             native.bazel_version)