Title: .rhevmshellrc Configuration

Describe the issue:

The .rhevmshellrc configuration requires section headers, if you don't have them it barfs. This isn't mentioned in the guide at all and it's left as an exercise for the reader to guess what they should be.

Traceback (most recent call last):
  File "/usr/bin/rhevm-shell", line 9, in <module>
    load_entry_point('rhevm-shell==3.4.0.6', 'console_scripts', 'rhevm-shell')()
  File "/usr/lib/python2.6/site-packages/ovirtcli/main.py", line 27, in main
    context = OvirtCliExecutionContext(sys.argv, parser)
  File "/usr/lib/python2.6/site-packages/ovirtcli/infrastructure/context.py", line 47, in __init__
    super(OvirtCliExecutionContext, self).__init__(args=args, option_parser=option_parser)
  File "/usr/lib/python2.6/site-packages/cli/context.py", line 75, in __init__
    self._load_settings()
  File "/usr/lib/python2.6/site-packages/cli/context.py", line 133, in _load_settings
    found, old_format = self.settings.load_config_file()
  File "/usr/lib/python2.6/site-packages/cli/settings.py", line 131, in load_config_file
    if not cp.read(fname):
  File "/usr/lib64/python2.6/ConfigParser.py", line 286, in read
    self._read(fp, filename)
  File "/usr/lib64/python2.6/ConfigParser.py", line 482, in _read
    raise MissingSectionHeaderError(fpname, lineno, line)
ConfigParser.MissingSectionHeaderError: File contains no section headers.
file: /root/.rhevmshellrc, line: 1
'username=admin@internal\n'