ci: travis: switch to newer distro releases
We follow Debian 9.9, Ubuntu 19.04 and Fedora 30 releases.
Also adding a build for Ubuntu 18.04 LTS to the cron job.
Not all jobs are updated yet as some experience failures
(old or new versions) which need to be understand and fixed
before we move on.
Reviewed By: zmike
Differential Revision: https://phab.enlightenment.org/D9088