Add "travis_retry" to our build to reduce transitory failures
Add "travis_retry" to our build to reduce transitory failures

Documentation is at https://docs.travis-ci.com/user/common-build-problems/#travis_retry

See https://github.com/docker-library/memcached/pull/14 for the test PR for this pattern.

snowair/php-docker,DoveConviene/php,iwat/docker-library-php,docker-library/php,infosiftr/php