[pbmserv-dev] new command suggestion

["Luke Pebody" <luke@monitorlizards.co.uk>]

<game> challengeanyone <player> <password>

When a game received such a message it would check to see if a partial
game already exists.

If it doesn't
 A partial game will be started, including the given player
If it does
 A check will be made whether the person is already part of the game
 If the person is
  An error will be returned
 If the person is not
  The player will be added to the partial game. If this completes the
  Required number of players, then boom-bang-a-bang the game starts.

Possible added functionality

<game> challengeforbid <player> <password> <otherplayer>
Will not add <otherplayer> and <player> to the same partial game. 
Then if one of them (say <otherplayer>) makes a challengeanyone request,
the computer will check:
1) Is <otherplayer> in a partial game already?
 If so, fail.
2) Does there exist a partial game in which <player> is not playing?
 If so, signup <otherplayer>
 Otherwise, signup <otherplayer> to a new partial game.

Other possible added functionality

<game> challengeanyone <player> <password> <codeword>
Only allow entry to the partial game from anyone else who uses the same
codeword. This allows challengeanyones within a certain clique. Further
it could be used in chess to make sure you challenge people around your
same skill level. Et cetera.