Added required as optional argument to get_bin_path(). It defaults to
false. Updated following modules to use required=True when calling
get_bin_path(): apt_repository, easy_install, group, pip,
supervisorctl, and user.
Also removed _find_supervisorctl() from supervisorctl module and updated
_is_running() to not need it.
* Migraed easy_install, pip, service, setup, and user.
* Updated fail_json message in apt_repository
* Fixed easy_install to not hardcode location of virtualenv in
/usr/local/bin/.
* Made handling of virtualenv more consistent between easy_install and
pip.
mpdehaan requested in ansible/ansible#795 that globals be removed.
The response was to remove the lines with the word 'global', but not
the actual use of global variables. Which makes the module break silently.
Updated to use local variables.
