Migrated app to modular Sinatra application; copied in a lot of improvements for a Sinatra app that I learned from Stage Manager

Rakefile

@@ -10,11 +10,11 @@ namespace :db do
 end
 
 namespace :server do
-  task :dev do
-    %x{ruby raven.rb}
+  task :start do
+    system("puma -C config/puma.rb")
   end
 
-  task :reload do
-    %x{rerun --no-notify 'ruby raven.rb'}
+  task :dev do
+    %x{guard}
   end
 end