1. Refactor the code for bindctl.
2. Update man page for bindctl provided by jreed.
3. Add more unit tests.
4. Need Review(When command line syntax is changed later, the following 
functions should be updated first.):
        bindcmd.py:
            apply_config_cmd()
            _validate_cmd()
            complete()
            
        cmdparse.py:
            _parse_params

        moduleinfo.py:
            get_param_name_by_position
5. Understandable error message when cert_file is missing.
6. Pick location to save default user. Or use the cfgmgr for this.
   If the default user is saved in file, its password shouldn't be saved in plaintext.
7. Need to think of what exactly to do with responses received to commands
   (currently it simply print the map)
