Missing cmake cache variables (#1090)

Summary: Pull Request resolved: https://github.com/facebookexternal/f4d/pull/1090

Reviewed By: laithsakka

Differential Revision: D28774321

Pulled By: kkeita

fbshipit-source-id: 2c8eb8edf69611e94bf124b52fc8c1e11df9b527

.travis.yml

+# 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.
 # Facebook projects that use `fbcode_builder` for continuous integration
 # share this Travis configuration to run builds via Docker.