Add Multilanguage support

[luzfcb]

A very useful feature for places where English speakers are a minority, such as in China, Brazil, Argentina, India.

I would be willing to translate it to pt-BR

in a quick search, apparently very little is prepared for translation https://github.com/pinax/symposion/search?q=ugettext&ref=cmdform https://github.com/pinax/symposion/search?q=trans&ref=cmdform