Fix sudo bin/cake install

Hi,

sudo bin/cake install doesn't work on my Ubuntu setup.

I've fixed two problems:
*  My user isn't in the same group as the root user. So the files copied to /usr/local/lib/coffee-script are not accessible to me.
*  My sudoers has always_set_home and so the coffee-script node module is installed in the inaccessible /home/root/.node_libraries rather than /home/username/.node_libraries [1]

regards,
--Will

[1] Even ~/.node_libraries isn't necessary readable by all users, so this is fixed as well.