Add sanity checks for code that uses SquaredDistanceTo in Holder.

A sanity check for different rooms which returns $ was added to SquaredDistanceTo() in holder.kod in the last update, unfortunately there were functions using this that either don't have both objects in the same room (yelling) or have cases where one object has $ room (casting an attack spell on a monster as it dies). This pull request fixes both those cases by not calling Sqdt() in both of those cases. There are other cases where this error may occur but these are the two most frequent, and I believe the check Gar put in place will likely catch more important errors (that we won't see in the log) than if it isn't there.