* Adds a default color hex value to the /admin/tags/show color picker
* Rebased against color-picker changes and adds default color to edit.html.erb
* Adds a system spec for admin/tags and adjusts the filename for admin_creates_new_page_spec
* Uses .blank? in place of .nil? in admin/tags/show.html.erb
* Refactors test in admin_updates_tag_spec.rb