Fix some translations in notifications
Set env[action_dispatch.exception] on nil in ErrorsController
Add user question and answer profiles to dia
Fix float to decimal in profiles
Refactor answer revisions
Refactor comment revisions
Refactor question revisions
Fix editable controller and test after revisions refactor
Refactor name of revisions
Merge pull request #54 from pavolzbell/revisions-refactor

Revisions refactor
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Update DB schema
Format DB schema diagram
Fix watchers for answer labeling
Update resource notes for activities and notifications
Fix link_to_evaluation helper
Use shorter icon names for followings
Add missing resource types to notification helpers
Include required concerns to all notification resource types
Fix read_at for all read notifications