Raw block bug fix

Removal of raw block causes issues so in the create/update actions, I iterated over ContentBlocks and if "raw" didn't exist, I would insert it. Also removed the delete button if ContentBlock type was 'raw'. 
This should be a validate call, so that things like valid? will return false.  Read the section on custom validations

http://guides.rubyonrails.org/active_record_validations.html