remove code path for bundling interface translations
remove unused options
proactively exclude mo files
Merge branch 'release-0.10.3' of github.com:learningequality/ka-lite into 1258
Merge branch 'release-0.10.3' of github.com:learningequality/ka-lite into 1258

Conflicts:
	kalite/i18n/management/commands/update_language_packs.py
Merge pull request #1269 from aronasorman/1258

Don't bundle interface translations.