Removes unecessary code
Merge branch 'bugfix/0.2.x'
Improves contidional to data validation
Fixes unique site, channel and slug validation
add @yacows notification via #slack
Change Django version requirements
Fix requirements
Remove unnecessary code for templatetags
Fix bug there is no polymorphism method
now the opps manager extends the polymorphism manager
reconvery opps manager
Used channel_id on container unique_together
Adds new messages and translation on URL TARGET
Merge pull request #349 from shuhikari/master

Adds new messages and translation on URL TARGET
update transifex
Updtae translate
Corrects locale