Add German language

[GSI]

I translated the yml's to German. What is the purpose/meaning of the 'mega:' element in them?

Also, how are the tests supposed to be run?

[kslazarev]

What is the purpose/meaning of the 'mega:' element in them?

In general (:en) case, ':mega' field include capacity names: [..thousand, million, billion, trillion..].
In some languages (:ru), ':mega' elements is names of the fields in language yaml file. In that fields we have some language customizations depends on pluralization, for example.

Also, how are the tests supposed to be run?

It's quite simple, just add/translate 'integer/fixture_examples/de.yml' in spec directory, as you already have done. And that's all. 'rspec, rspec, rspec'. If you want to focus only on your language, replace line (numbers_and_words_spec.rb:7) by:

[:de].each do |locale| 

Updated: I merge all your commits in 'feature/german' branch. There are some changes in the project's architecture. Use that branch instead to continue development.