generated pin resource
created pins table
set up create and destroy action for pins controller
set up pin model associations
fixed typo on pin route
set attributes in pin#create
set up a helper method for pin link on post show
changed post_pin_link helper method to show successLink if pinned
use content tag to replace html_safe in post link helper methods (also fixed delete link)
fixed link on home#index banner
use content tag in form error messages helper method
take out html safe on post form cancel link and use content_tag instead
added header to post form