ANSIBLE_DIST_MODULE_PATH environment variable
use DEFAULT_MODULE_PATH in setup.py so that there is a chance to override with ANSIBLE_LIBRARY env variable
Make ssh's ControlPath configurable via ansible.cfg

This shouldn't generally be needed unless you're working in an environment
that uses rediculously long FQDNs; if the name is too long, you wind up
hitting unix domain socket filepath limits enforced by ssh.
Update CONTRIBUTING.md
Adding example section to ansible.cfg for the control_path setting
Added Python 2.4 support to modprobe module