Closes #212 updating README to explain how to use hooks with git templates

Also cleaned up README format (within 80 char/line)
Fixes #206 an issue with hook enable/disabling and shebang detection
Adding TODO for issue #219
Closes #196 fixing PATH issue with hook when ran from Git GUI Clients

Also, this fix most likely closes many other issues around the same
problem, will try to verify on various clients.