Rename __init__ options argument for clarity

The first argument to __init__() after 'self' is named 'sosreport'
however it contains a Python options object:

{'loglevel': 'INFO', 'reporting': False, 'ipv4': False, 'sosreport': None, 'ipv6': False}

Passing this down as a filename through _prep_environment leads to:

    return _file(self._magic_t, filename)
ArgumentError: argument 2: <type 'exceptions.TypeError'>: wrong type

Rename the argument to 'options' and extract the 'sosreport'
option as a string before calling _prep_environment().

Signed-off-by: Bryn M. Reeves <bmr@redhat.com>
Convert python to use native libmagic python-magic bindings

There are two Python modules calling themselves 'python-magic'.
One is part of the upstream file / libmagic project (this one is
shipped in Fedora and other Red Hat distros). The other is a
standalone cPython wrapper that has a different API.

Convert the SOSCleaner code to use the libmagic bindings when
determining file types.

Signed-off-by: Bryn M. Reeves <bmr@redhat.com>
Merge pull request #11 from bmr-cymru/bmr-libmagic-fixes

libmagic fixes and __init__ cleanup