Allow attributes, skills and spells to be viewed in replays

[tung]

Right now, it's impossible for a person viewing a replay to see what attributes, skills or spells the character in play currently has. Using the usual commands to view this info during a replay (i.e. Ctrl-X, #enhance, Z/+) has no effect, since these commands lack the CMD_NOTIME flag, which nh_command() forbids the use of by viewers during a replay.

One way to fix this would be to supply an optional replay-safe function for commands alongside the usual function which would run when the viewer (not the replay system!) issued commands while watching a replay. This would replace the check for CMD_NOTIME, reserving it purely for marking that a command should not be logged.