module Rails::Command::Actions

def set_application_directory!

the main config.ru and properly set the tmp directory.
This allows us to run rails server from other directories, but still get
Change to the application's path if there is no config.ru file in current directory. 
def set_application_directory!
  Dir.chdir(File.expand_path("../..", APP_PATH)) unless File.exist?(File.expand_path("config.ru"))
end