improvements to the memory debugger to report more information in
case of errors. Also, some allocations that occured through
REALLOC couldn't be previously catched correctly..
(some platforms don't provide this ANSI function !!)
some changes to "ftsystem.c" implementations in order to use
the new memory debugger on Unix, VMS and Amiga too !!
the debugging memory manager to report the location (source file name
+ line number) where leaked memory blocks are allocated in the source
file.. funny, isn't it ??
