Updates to Ansible command options
* Moved the --list-hosts option that is common to both `ansible` and
  `ansible-playbook` into utils/__init__.py (corrects a FIXME)
* Wrote new help text for the --list-hosts option that makes sense
  for both of the commands that it applies to
* Changed the usage argument in `ansible-playbook` so that it is
  setup in the base_parser method the same way that it is in
  the `ansible` executable
* Updated the help text for several options to correct typos,
  clarify meaning, improve readability, or fix grammatical errors.
  In the case of `ansible-pull`, I changed the help text so that
  it adheres to the same standards as the other executables.
Merge branch 'option-updates' of git://github.com/jlund/ansible into devel

Conflicts:
	bin/ansible-pull