Migrate build-jobs to travis-ci.com

[ferraith]

From a build perspective setuptools-pyecore is a legacy project which is still hosted on travis-ci.org. The guys from Travis CI are currently replacing the legacy travis-ci.org platform with the new travis-ci.com platform (see Open Source on travis-ci.com). In Q3 also legacy projects will be migrated to travis-ci.com. In this ticket the migration should be tracked and necessary configuration changes (e.g. check and status api) should be applied to this project.