CLI: Switch authentication library to use request module

The auth library in node-appc uses node's built-in http client which does not support proxy servers. We need to rip out node's http request library and use the "request" module like we do everywhere else.

Users in the Q&A are having problems logging in: http://developer.appcelerator.com/question/146837/unable-to-login-with-titanium-cli-version-3022.