Implement ConsoleOutputFormatter that is backward compatible
with the previous implementation.
Implement JUnitOutputFormatter which can be added externally.
* Fix kqueue.nim and ansi_c.nim to support dragonfly.
* Fix ioselectors.nim, threads.nim to support dragonfly.
* Fix deprecated dealloc call in tioselectors.nim.
* Fix tfsmonitor.nim test to run only on Linux.
* Fix osproc.nim return wrong exit codes.
* Fix getAppFilename() for dragonfly.
* Fix proper exit code handling.
Having a lexicographically sorted collection is a big benefit (I asked GvR years ago to add one to Python but it was no then and seems to be no now!).
Anyone looking for a such a collection could easily miss the critbits model because very few people have heard of them (according to Wikipedia most people in a ration of approx 750:1 know them as radix trees: https://en.wikipedia.org/wiki/Talk%3ACrit_bit_tree).
* Fix 2 problems. First, 0 is a valid fd on Unix (easily gotten if user first
closes all fds and then starts using memfiles). Use -1 instead for an invalid
fd. Second, it is best practice to conserve open fds on Unix and file handles
on Windows. These handles are not needed unless the user wants to remap the
memory with ``mapMem`` (or a hypothetical future ``proc resize``). Adding a
new bool param ``allowRemap=false`` to ``memfiles.open`` solves this cleanly
in a "mostly" backward compatible way. This is only "mostly" because the
default ``false`` case does not keep unneeded resources allocated, but that
most sensible default means that any ``mapMem`` callers need to fix all their
open calls to have allowRemap=true, as this PR also does for tmemfiles2.nim.
* Include backwards compatibility note.
