update model specs for Comment to test self-join association
add migration for adding parent_id to comments
add specs for has_many :replies for comments
add self-join association for comments
add specs for testing replies to comments
fix specs for replies
add reply routes
fix specs for replies
add #new_reply to CommentsController
add new_reply.html.erb
update new_reply form
add #reply_params in CommentsController
add #reply to CommentsController
delete unneccary test
delete unneccary query
fix spec mistakes
fix #reply creation in CommentsController
add link to reply a comment
add pending specs for redirect after create_reply
fix _single views for comments to properly display replies