everything shoud have a 'readable_id' property
update gitignore with 'v' (virtualenv)
Reinstated new homepage
removed 'related exercise' support in main catalog
track exercise progress in user-css
logging update
remove deprecated cron jobs
bug fix in map reduce calls
Update user exercise progress to usercss
update css version
removed subtitles support from videos
style changes to navigator
bug fix in alerting on dup children
wip
page-based nav
wip