RESTful Router

Router now allows you to specify what HTTP method the route should
respond to (GET, POST, DELETE, PUT).
Moved Router to Common

Added 'METHOD' as a global constant. Primarily for security so that a
filter can't change what route is used.
Autoloader gracefully fails

If the autoloader can't find the file, it returns false and lets the
next autoloader try (i.e. Composer).