adds plugin_storage to Player

 this totally un-normalized json string based field can be used by plugins to store information about this player. Kept in a seperate namespace per plugin.
initial commit of new_player_greeter
allows plugins to store abitrary objects
adds commands to promote/demote players
Got everything nice and sorted out. Made a general purposes utility file. Any functions that may be static and can possibly be used for general purposes should probably be migrated here.
Merge branch 'MrMarvin-player_plugin_storage'
Fixed a few bugs, merge complete.
Moved starter items to text file.
Broke out build_packet into the utility functions script.
Updated the documentation and refactored a few variable names.
adds BouncerPlugin...

... that prohibits new players (as in UserLevel < REGISTERED) from
destructive actions
Merge pull request #18 from MrMarvin/bouncer_plugin

adds BouncerPlugin...