minor reviewing of autentication

[starnutoditopo]

In this changeset:

1. I added a .hgignore file (just because I use Mercurial; nothing interesting, here)
2. I updated package.json (to use newer versions of some components; nothing interesting, here)
3. I had a quick review of the object returned in js/using_apis.js. Note that this is not a fix, but just an attempt to verify where the error is.
   Probably, the fix would consist to modify the function is_auth_error (lines 27 - ), so that it would inspect err.status.signed_in and err.status.google_logged_in, instead of testing for things like: err.status > 200, etc