New release v0.3.0
New release v0.3.0

Highlights:

 - Removes support for string and numerical array responses in
   `Lily\Adapter\HTTP` but maintains support in
   `Lily\Application\RoutedApplication`
 - Breaking changes to Response API, the `$header` and `$body` swapped
 - Adds `Lily\Middleware\ExceptionHandler`
lukemorton/lily,lukemorton/lily,DrPheltRight/lily,DrPheltRight/lily