[Localization] Serbian translation for NetworkManager

[Filip Miletic <filmil gmail com>]

Hello all.

Please be so kind to accept the Serbian translation for NetworkManager
and include these files in the distribution.

As the Serbian language can be written down equivocally with two
different scripts, the Cyrillic and the Latin, two translation files are
provided. The language labels follow the conventions adopted elsewhere
in GNOME.

http://cobalt.et.tudelft.nl/~filip/files/tran/NetworkManager/sr.po
http://cobalt.et.tudelft.nl/~filip/files/tran/NetworkManager/sr Latn po

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