i18n: update translation from transifex

ui/bg.lproj/AccAdvanced.strings

ui/bg.lproj/AccAudio.strings

ui/bg.lproj/AccGeneral.strings

ui/bg.lproj/AccRing.strings

ui/bg.lproj/AccSecurity.strings

ui/bg.lproj/AccVideo.strings

ui/bg.lproj/Accounts.strings

ui/bg.lproj/AudioPrefs.strings

ui/bg.lproj/CertificateWindow.strings

ui/bg.lproj/Conversation.strings

ui/bg.lproj/CurrentCall.strings

ui/bg.lproj/GeneralPrefs.strings

ui/bg.lproj/Localizable.strings

ui/bg.lproj/MainMenu.strings

ui/bg.lproj/PersonLinker.strings

ui/bg.lproj/PreferencesWindow.strings

ui/bg.lproj/RingWindow.strings

ui/bg.lproj/RingWizard.strings

ui/bg.lproj/VideoPrefs.strings

ui/ca.lproj/AccAudio.strings