Fix for #1158: eliminate need for LanguagePack model (but keep the model, for future use)
removing admin display of language packs, since they are empty
Localize the reloading of session data, to avoid programming errors.
Merge pull request #1279 from bcipolli/1158

Fix for #1158: eliminate the need for the LanguagePack model
do not include crowdin-cached files in KA Lite zip
fix issue #1251: remove calls to sudo in scrape_videos
place youtube-dl in /scripts instead of /data/scripts
Merge pull request #1283 from aronasorman/1251

fix issue #1251: remove calls to sudo in scrape_videos
Merge branch 'develop' of github.com:learningequality/ka-lite into i18n_cleanup_2

Conflicts:
	kalite/management/commands/zip_kalite.py