facebook meta locales (step 1)

the default social meta data needs translating

**steps:**
1) extract translation so community can translate
2) tune app so FB scrapes and displays locales correctly

step 2 looks like it might be fidely, want to focus on doing that once we have some foreign strings to play with.

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**notes for future**
- fb may attach param `fb_locale` when scraping
- fb might expect _downcase underscored_ locales instead of _mixed-caps hyphen_ locales  (e.g. `pt_br` over `pt-BR`). We might need to reconsider our opinion about our default (currently we bend to the hyphen because that's the format of browser request headers)

**resources:**
- https://developers.facebook.com/docs/opengraph/guides/internationalization  
- http://stackoverflow.com/questions/7614603/facebook-meta-tags-scraped-with-locale-not-working#_=_
- https://www.facebook.com/translations/FacebookLocales.xml