cli.py:  more meaningful messages on server exceptions

Make it clear that the exception originates server-side, and don't
trim the string, which may not be enclosed in quotes
utils.py:  fix set_virt_type() when value is <<inherit>>
koan/app.py:  get .ks file from --server host, not profile data

The profile's 'server' attribute address may not be addressable by the
VM host for retrieving the kickstart file to obtain install tree
information.

Instead, retrieve the kickstart file from the cobbler server specified
in the '--server' argument.
koan/app.py:  handle kickstart url '--proxy' argument

'--proxy' is a valid argument for the 'url' and 'repo' kickstart
options:

  url --url http://repos.example.com/repo --proxy=proxy.example.com:3128
koan/utils.py:  fix subprocess_get_response() to work with python 2.6

subprocess.check_output() was introduced in python 2.7, but EL6 is on
python 2.6.

Use the basic Popen() instead.
setup.py:  fix man page install source glob
utils.py:  add option default to add_options_from_fields() choices

If the default option is not in the option list, add it.

Most notably, this adds '<<inherit>>' as a choice to many options with
a fixed list of choices.
Add source /etc/sysconfig/cobblerd to init script