Added Serbian Cyrillic, Serbian Latin and Croatian, thanks Zsolt!
Don't bump installation version yet
Merge branch '2.5.x-serbian-croatian' of https://github.com/danielhjames/Airtime into 2.5.x

Conflicts:
	airtime_mvc/locale/hr_HR/LC_MESSAGES/airtime.mo
	airtime_mvc/locale/hr_HR/LC_MESSAGES/airtime.po
	airtime_mvc/locale/hu_HU/LC_MESSAGES/airtime.mo
	airtime_mvc/locale/hu_HU/LC_MESSAGES/airtime.po
	airtime_mvc/locale/sr_RS/LC_MESSAGES/airtime.mo
	airtime_mvc/locale/sr_RS/LC_MESSAGES/airtime.po
	airtime_mvc/locale/sr_RS@latin/LC_MESSAGES/airtime.mo
	airtime_mvc/locale/sr_RS@latin/LC_MESSAGES/airtime.po