add rvmrc_create method

[DanielKehoe]

I'm using the API in a Rails application template to set up an rvm gemset when an application is created with the rails new -m command. I appreciate being able to use the API method RVM.gemset_create app_name. I also want to create a .rvmrc file using the API. I can do this in my application template using Thor commands:

  create_file '.rvmrc' do
    "rvm #{rvm_env}"
  end

but I like the full-featured .rvmrc file I get when I use $ rvm --rvmrc --create ruby-1.9.3-p194@myapp in the shell.

I was expecting to be able to use an API method like RVM.rvmrc_create "default@mygemset" but after scanning the source code I don't see any methods to create an .rvmrc file in the API. Did I overlook it or is it missing? Would it make sense to add it?

[mpapis]

Closing as this will be provided as part of RVM 2.