Pontoon: Update Bulgarian (bg) localization of Firefox Screenshots
Pontoon: Update Bulgarian (bg) localization of Firefox Screenshots

Localization authors:
- Stefan <a582hs@gmail.com>
- :stoyan <stoyan@gmx.com>

mozilla-services/pageshot,mozilla-services/screenshots,mozilla-services/pageshot,mozilla-services/pageshot,mozilla-services/pageshot,mozilla-services/screenshots,mozilla-services/screenshots,mozilla-services/screenshots