Use passphrase-less SSH keys.
Update script to work with Ubuntu 13.04 / Ruby 2.0.0 combo.

  * Update library dependencies for Ubuntu 13.04 / Ruby 2.0.0-p0

  * Use latest RVM install procedure.

  * Use Ruby 2.0.0 patchlevel 0.

  * Change cURL output mode.

  * Change Heroku toolbelt installation procedure.
Prettify information messages.

  * Create a function to display info messages colored and w/
  some formatting. Replace all 'echo' information outputs with that.

  * Add small function to compute ellapsed times: Display at end.
Update README to reflect latest test/version working.