This is a stupid simple gem which you can use to trigger a rebuild on Travis Pro. It could likely be enhanced without much effort to work on the public system as well but I have no use for that at this time.
DO NOT use this tool to compensate for a piece of crap test suite that fails depending on the cycle of the moon. Fix your tests instead. Valid use cases are when a test suite fails because a worker died, code couldn't be checked out because GitHub had a temporary issue, etc.
gem install travis_reprise travis_reprise USER REPO BRANCH