Removed CanCan from project
Revert "Removed CanCan from project"

This reverts commit f3a68405bad4fc33b7f2b54713f297a62f36cc06.
Revert "Revert "Removed CanCan from project""

This reverts commit b337e22779bca69a38b561f34f83a33bebd615f4.
Implement authorisation with Pundit