Add new routine 're_alloc()' that functions as MONITOR_HEAP-aware
libc realloc(). 'nhrealloc()' is the version that passes source
file and line info if built with MONITOR_HEAP enabled. The heaplog
data might now contain '<' (freed by realloc), '>' (replacement
allocation by realloc), and '*' (resized by realloc) entries in
addition to the previous '+' (allocated) and '-' (freed) entries.
heaputil has already been updated in the NHinternal repository.
Move FITSint_() and FITSuint_() from hacklib.c to alloc.c so that
they can be accessed by miscellaneous utility programs.
Remove three or four copies of FITSint_() that were duplicated in
utility programs like dlb and tile2bmp due to those not having
access to src/hacklib.o. They do have access to src/alloc.o (and
util/panic.o).