Center page header
Create AdminUser model
Implement sign-in for admin users
Authorize creating and showing guides
Add CircleCI build status badge
Upgrade to Rails 4.2.0.beta3

Raisl 4.2.0.beta2 had a security vulnerability, as described here:
http://seclists.org/oss-sec/2014/q4/474
Set page-specific controllers in route definitions
Update angular-material and theme
Update toast button margin
Reset new guide content with Angular
Fix md-content padding
Refactor and add padding to new guide preview
Make title and body required in guide form
Add edit guide functionality
Use indigo-themed admin login buttons
Fix NameError in new guide view
Use a flex span to push header buttons right
Set theme on body tag
Remove unnecessary layout setting
Change up some lines