semenage-argparse: Now with full help test (except -E) and support for the login subcommand

[David Quigley]

Hello,
    I added more help text to the semanage-argparse rewrite and also 
implemented support for login. I would like anyone and everyone to look 
at the code and give me feedback. I am in no way shape or form a python 
guru so I'm glad to have any and all constructive feedback. Please let 
me know what you think.

https://github.com/dpquigl/semanage-argparse/

Dave