v0.5.0

Initialization of a songs directory is now easier, as mtrack can be given an --init flag
when using the songs subcommand. This will establish a baseline YAML file in each song
directory.

Live MIDI can be routed to the DMX engine. This will allow live controlling of lights through
mtrack.

The playlist can now be specified through the mtrack configuration YAML rather than specified
separately when using the start command.

Simple MIDI to DMX transformations are now supported. This allows for a simple MIDI event to
be expanded into multiple, which can then be fed into the DMX engine. This allows for things
like simple MIDI controllers to control multiple lights.