Update rails to 4.2
Merge branch 'develop'
Remove fluentd
Minor change for fluentd host
Merge branch 'develop'
Minor fix
Merge branch 'develop'
Change name
Add feedback model
Support adding sample data
Add controller and view for feedback
Support creating feedback
Polish UI at feedbacks view
Minor fix
Show description as markdown
Minor change
Support markdown preview
Support editing feedback
Support anonymous user
Allow iframe