Use `run` instead of `sudo` when running as root

This makes it easier to use fabtools on target systems where
sudo is not (yet) installed.

The recommended usage is still to connect to the target system
using a regular user account (e.g. `admin`) that can acquire elevated
privileges only when necessary using `sudo`.
Clean up imports
Upgrade default Redis version to 2.6.10
Upgrade default Node.js version to 0.8.19
Prepare 0.11.0 release