change rspec match_regex -> match

Signed-off-by: Dominik Richter <dominik.richter@gmail.com>
bugfix: correct negation by 'to should_not' -> 'to_not'

Signed-off-by: Dominik Richter <dominik.richter@gmail.com>
bugfix: use simple ruby tests for custom rspec matcher

Signed-off-by: Dominik Richter <dominik.richter@gmail.com>
Merge pull request #23 from TelekomLabs/fix-matches

Fix matches