[WIP] Feature descriptive languages

So, the main idea is instead of detecting languages separately for different parsers and make parsers translate dates on their own, we detect and translate dates outside of parsers and make parsers operate strictly on English dates. Parsers code became very simple because of this and it would also make much more easier to add new parsers if we would ever need to.

Branch in its current state lacks majority of tests, but all functionality is in place. Also as you can see in `languages.yaml` file, adding new languages is very easy.

This request targets issues #9 and #12.
Because initial behavior of striping anything beside timezone itself was wrong and does not work with some of the languages.