Rename the S3 provider to just S3

liquor-cabinet.rb

@@ -5,7 +5,7 @@ require "sinatra/base"
 require 'sinatra/config_file'
 require "sinatra/reloader"
 require "remote_storage/swift"
-require "remote_storage/s3_rest"
+require "remote_storage/s3"
 
 class LiquorCabinet < Sinatra::Base
 
@@ -132,7 +132,7 @@ class LiquorCabinet < Sinatra::Base
       if settings.respond_to? :swift
         RemoteStorage::Swift.new(settings, self)
       elsif settings.respond_to? :s3
-        RemoteStorage::S3Rest.new(settings, self)
+        RemoteStorage::S3.new(settings, self)
       else
         puts <<-EOF
 You need to set one storage backend in your config.yml file.