fix, PEBKAC, adhere to mmap() POSIX specs and use -1 for fd on memory maps

Signed-off-by: Sebastian Freundt <freundt@ga-group.nl>
fix, try to be more honest about aliased pointers, {re,un,up}size_*() by value instead of by reference

Signed-off-by: Sebastian Freundt <freundt@ga-group.nl>
Merge branch 'fix/general' into next

* fix/general:
  fix, try to be more honest about aliased pointers, {re,un,up}size_*() by value instead of by reference
  fix, PEBKAC, adhere to mmap() POSIX specs and use -1 for fd on memory maps
Merge branch 'next'

* next:
  fix, try to be more honest about aliased pointers, {re,un,up}size_*() by value instead of by reference
  fix, PEBKAC, adhere to mmap() POSIX specs and use -1 for fd on memory maps
  doc, clarify the 2 truffle modes' purposes
  fix, provide a proper multiline Usage for truffle
  fix, PEBKAC, for non-mremap() case in resz_gbs() actually munmap() the old array