Installed the Aura Router package.
Standardised directory variables and functions in the App class.
Updated version of MattyG.Http module in use.
Added routing to the framework!

Routing is provided by the Aura.Router module. Routes are defined in
src/app/routes.php. I still need to setup caching for the routes, as
generating the list could get quite costly if you have a lot of routes.

The 404 page still needs a bit of work.
Bumped the version number to 0.3.0 and updated the readme file.