[Python] Command line / argument parsing (from a string)

[MattIPv4]

Drop the terminal debug system and replace with a command line for control.
Command line should be in its own sub package so that it can be used in both a terminal debug mode and via the web debug control in #5
The command line should support access of global callbacks, fixture helpers, fixture colors and individual fixture channels.
Additionally, support for selecting groups of fixtures and then using fixture helpers/colors/channels would be a plus.

[MattIPv4]

Please note, this should be a command line implemented inside the package, not as arguments for a python file.
Preferably the command line should be as english as possible, the use of flags would not be encouraged.
Eg 'select fixture 5' not '--fixture 5'