added ruby 2.0 to travis and fixed mofile for ruby 2.0

i added ruby 2.0.0 to travis and finally fixed the mofile errors i was getting from the start.

i used the mofile from your fastgettext gem to fix the errors in get_pomo. 

the singular.mo spec is still not working, but that should be due to malformed encoding and no encoding header set in the mo file. ruby > 1.9.0 seems to be more strict than ree.

the complex mo file also uses umlaute and is working fine (probably due to the encoding header set)