empdump exports and imports game state as plain text. Limitations: it
currently can't export player bmaps, power report, telegrams,
announcements, message of the day, no-login message and log files.
Exported floating-point values may be inexact. Importing an exported
game state may not result in identical data files; besides the loss of
floating-point precision just mentioned, coordinates are normalized,
and characters beyond a string's terminating zero in a character array
are lost. Bug: importing resets timestamps to zero. It should set
them to the current time.
