Allow lxc module to work on both Ubuntu and Redhat

Per Issue #10230 lxc module changed to work on both Redhat and Ubuntu distros.

Summary of changes:
  - Use lxc-version rather than lxc to detect if the software is installed
  - Rewrote the list_ function to use lxc-ls and lxc-info directly to get the data rather than rely on the lxc-list script to exist

Tested on 
CentOS 6.4
Ubuntu 12.04