Suggestion: Set up Travis CI to test multuple platforms and ICU versions

Created by: SethMMorton

I note that this repository has a .travis-ci.yml file, but based on a comment in another issue this repository is not actually connected to Travis-CI.

As a first step, I would recommend connecting this repository to Travis-CI (if I recall it is very simple). This way, it can be seen if the .travis-ci.yml currently in the repo is even valid.

If this is set up, I (or someone else) can submit a PR to help update the .travis-ci.yml file to support multiple platforms and multiple ICU versions, so that finding bugs before release is much simpler.