Add Sinatra::Reloader for development
Add Sinatra::Reloader for development

This adds Sinatra::Reloader enables it when in development. Sinatra::Reloader
will automatically reload classes/files on change in development, so you don't
need to start/stop the server to pick up changes.

neilmiddleton/pliny-test,uhoh-itsmaciek/transferatu,ukd1/transferatu,uhoh-itsmaciek/transferatu,ukd1/transferatu,heroku/pgperf,heroku/pgperf