proper maintenance target
addded .travis.yml
fixed tests
removed RegistrationStatus.pm module

obsolete, not supported by the new SCC registration

- 3.1.110
updated *.spec file
Merge pull request #303 from yast/RegistrationStatus_dropped

removed RegistrationStatus.pm module
run more checks at Travis

- `rake check:syntax`
- `rake check:pot`
Merge pull request #304 from yast/Travis_check

Run more checks at Travis
added more checks in .travis.yml
Merge remote-tracking branch 'origin/SLE-12-GA'

Conflicts:
	.travis.yml
	Rakefile
Remove support for the unmaintained GTK UI plugin