use proper Puppet version env variable name
remove too old puppet version from .travis.yml
add dependency on hiera-puppet for puppetversion lower 3
fix typo in Gemfile

still working on puppet 2.7 stuff
travis improvements:

- remove non working puppet versions
- add newer puppet versions
- remove excludes
- add newer ruby versions
travis cleanup

- exclude tests with old puppet versions on newer ruby version
travis fix:

build hash in exclude correctly
travis fix 2:

- typo was not in hash, but on rvm line itself - 2nd fix
travis fix 3: - use proper env variable name for puppet version
travis fix 4 - build proper hashes for excludes
Merge pull request #112 from tuxmea/travis_fix

use proper Puppet version env variable name