Added arrow as back button before 'Editing Post'.
Updated back icon on admin/posts/edit to use a thin chevron.
Adds help text to admin/posts/_form, Adds new button to admin/posts/index, admins/posts/new is consistent with admin/posts/edit.
Adds hipsterjesus.com API to admin/posts_controllers.rb, uses API to get placeholder text for admin/posts/new.