Add shoulda-matchers gem
Refactor validation tests for shoulda-matchers
Add current_user helper method for retrieving authenticated user
Change link to signout when authenticated
Remove unused images/edit view
Remove extra th on images/index
Make only UsersController index & show actions accessible
Add basic validation to Image model
Add User has_many Images association
Add default value to image.views
Add image factory
Eager load user association by default
Remove view tests
Only allow owner of image to destroy image
Return unauthorized response on destroy if current user is not owner of image
Allow only authenticated users to create new images