Initial CMS work for pages

Start of work on a content management system for pages on the
website.  Based heavily off of @rickgrundy's chunks CMS
(https://github.com/rickgrundy/Chunks).

Still a large WIP, more to come soon.
Implement block rendering and markdown blocks
Refactor pages to use a seperate admin controller

This will make the upcoming admin interface changes much
easier to manage.
General cleanup - remove unused files
Page admin fixes
Remove content from pages (now in blocks)
Pages admin panel can now add blocks

UI is still a bit messy, but the functionality is there
Page edit UI improvements, working deletion
Fix index of sub-pages
Support for multiple layout types
Move layouts and blocks into folders
Bootstrap tweaks
Form style improvements
Update ruby and rails
Merged with pages branch to ensure compatibility