dev-python/pyghmi: blocker older cli_helpers (bug 636824)

dev-python/pyghmi: blocker older cli_helpers (bug 636824)

This fixes the following build failure:

>>> Compiling source in /var/tmp/portage/dev-python/pyghmi-1.0.22/work/pyghmi-1.0.22 ...
 * python2_7: running distutils-r1_run_phase distutils-r1_python_compile
/usr/bin/python2.7 setup.py build
ERROR:root:Error parsing
Traceback (most recent call last):
  File "/usr/lib64/python2.7/site-packages/pbr/core.py", line 111, in pbr
    attrs = util.cfg_to_args(path, dist.script_args)
  File "/usr/lib64/python2.7/site-packages/pbr/util.py", line 267, in cfg_to_args
    wrap_commands(kwargs)
  File "/usr/lib64/python2.7/site-packages/pbr/util.py", line 569, in wrap_commands
    cmdclass = ep.resolve()
  File "/usr/lib64/python2.7/site-packages/pkg_resources/__init__.py", line 2415, in resolve
    module = __import__(self.module_name, fromlist=['__name__'], level=0)
ImportError: No module named tasks
error in setup command: Error parsing /var/tmp/portage/dev-python/pyghmi-1.0.22/work/pyghmi-1.0.22/setup.cfg: ImportError: No module named tasks

See: https://github.com/dbcli/cli_helpers/issues/25
Closes: https://bugs.gentoo.org/636824
Package-Manager: Portage-2.3.13, Repoman-2.3.3