charging rings

charging rings

     Reported--more or less--by <email deleted>:
chargeable rings don't show up as likely candidates in the "what do you
want to charge?" prompt.  They're supposed to be there once the type has
been discovered but it was using the wrong field so basing that on whether
the player had assigned a name to the type instead.  (Picking a chargeable
ring's letter even though it wasn't listed did work correctly though.)