Extract talk range calculation
Remove obsolete findAllAliveCharactersInRangeOfOnSameMap
Allow modification of z range in character search
Limit some character searches to one level

* Limit introducing to one level
* Limit possible monster targets to one level
* Limit whispering to one level (mantis issue #9509)
Remove duplicate code
Fix LOS algorithm
Do not remove monster from spawn when out of range
Use clearer variable name
Pass ScriptItem to depot script