Translation Changes

Modifications to how translations are built to support weblate. Gettext .po files are converted to QT .ts files when make translations is run.
Current Status:
 - [x] make translations is seamless; no build system changes required
 - [x] make translations_update updates the template .pot and all language .po files based on current code
 - [x] [Weblate Instance](weblate.robotbrain.info) exists and works (ON THIS BRANCH)
 - [x] Translate UI files (IMPORTANT)

Fixes #426