Merge pull request #23 from kobliha/master

Fixes and small refactoring
do not use *.spec.in template

use *.spec file with RPM macros instead

- 3.0.2
3.1.0
Add rakefile
adapt rakefile to use yast rake config
add license text
Add CONTRIBUTING.md

See:

  * https://github.com/blog/1184-contributing-guidelines
  * http://lists.opensuse.org/yast-devel/2013-10/msg00052.html
release package to fix factory build