Fix up license headers and Python linting

This will help [] be submitted without breaking the linter.
License headers are now added automatically where they were previously
added by hand. We're also now adding the license header to Soy and SQL
files.

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=129017424

java/com/google/testing/builddefs/GenTestRules.bzl

@@ -12,22 +12,6 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-# -*- mode:python; -*-
-#
-# Copyright 2016 The Domain Registry Authors. All rights reserved.
-#
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-#    http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
-
 """Generate java test rules from given test_files.
 
 Instead of having to create one test rule per test in the BUILD file, this rule