Please add in 'Brazilian portuguese' (pt_BR) into Switching Languages button

[Enrico Nicoletto <liverig gmail com>]

I observed that the behaviour associated to the  'Switching Languages' 
button has changed in
GNOME webpage, but my locale, Brazilian Portuguese (pt_BR), is not an 
option available in the list of languages.

Actualy only English, Spanish, German and Chinese are available.

Brazilian Portuguese have a good number of documentations translated but,
please, let us know if we can even improve our translations in order to make
it available in this list too.

Thank you all,
Enrico.