Add Activity model and Notifications::ActivityFeeder
Remove resource concern
Refractor ActivityFeeder
Add activity tab to user profile
Add default scope for Activity
Remove duplicated code, formating
Fix formating
Create activity for every resource
Add tests for activities
Remove followings from User model which were moved to Followings
Rename Notifiable to Evantable
Overide default scope from Deletable
Don't show Favorite activity
Revert "Rename Notifiable to Evantable"

This reverts commit 1d4db876bebd3ac9ec8bca47907aaa5d6c9387a6.

Conflicts:
	app/models/activity.rb
Following and Watching are Notifiable
Migration to add created_on to Activity
Add migration to add Deletable to Watchings and Followings
Update DB schema diagram
Add updated_on column to Activity
Replace destroy with mark_as_deleted_by!