Adding use statement
New RouteLoaderFactory class for handling the "magic"
of automatically inferring RouteLoader creation
New method for getting the directory of the tests
New `prepare()` method for the main Paulus class,
so that a few things can be loaded right before run time
but may also be injected or prepared manually if need be
Also, a new exception to be raised if the app is attempted to
be prepared and has already been prepared