Templating rework: No more layer - implemented a Templating Engine interface and associated classes.
Added shorthand render() method.
Updated configuration to match new templating system.
Update display of error codes.
Add the generateUrl method to generate URLs for routes.
Changed exception handling to catch exceptions even for outgoing layer processing.
Removed old Twig handling system - TwigLayer & TwigResponse. RIP.
Fix visibility modifier.
Fixed docblock-namespace declaration spacing.
Made the render() method return a wrapped response.
New templating system means twig is now not a requirement.