- Conversion from player to user types
- Conversion from player to user types

- Added a 'usage' attribute to the command class

- Fleshed out the 'play' command

- Moved context object generation to the start() phase so we can grab a
  reference to the containing stream object, too.

- Added cleanup to the stop() phase to release context and stream references.

--HG--
extra : convert_revision : svn%3A39a105f4-52d6-0310-bb1b-d6517044f2e4/trunk%40138

ged/mues