Generate packages using PackageCore and Travis CI

[jarun]

We had just started using BytePackager to auto-generate release packages for several Linux distros. Unfortunately the service is going down. However, the author was kind enough to share his source. Excerpt from his mail:

I have documentation at
http://packagecore.readthedocs.io/en/latest/02_intro/ (though there's
certainly room for improvement). If you have any specific questions, let
me know, as it will be helpful in determining where I need to flush out
the documentation.

I have one of my projects set up to build packages and upload to github
with PackageCore and Travis-CI that may be helpful (see the
`.travis.yml` and the `packagecore.yaml`):
https://github.com/dlasalle/wildriver

Distributing the release packages helps us reach many users immediately.

Can anyone take this up please?

[professorjamesmoriarty]

@jarun I believe I can structure the changes, and open a PR accordingly. It'll take a few to test before pushing to the repo. Good news is the secure key and the settings currently in place can be used with ease. As for other projects you may need to generate a secure key.

[jarun]

That's great! Yes, I guess I'll have to generate some more keys for the other projects but that's absolutely fine.

Please take your time. I'm in no hurry for a release.

[jarun]

@shaggytwodope fedora 26 support is in now. Let's have it! Dump fedora 25. ;)

[jarun]

The changes are working fine for googler (adapted). Closing the issue.