This breaking API change allows us to explicitly generate EOF when the
taken writer is dropped.
The examples have been updated to show how to manage read, write
and waiting without deadlock for both linux and windows.
Need to confirm that this is still good on macOS, but my
confidence is high.
I've also removed ssh2 support from this crate as part of this
change. We haven't used it directly in wezterm in a long while
and removing it from here means that there is slightly less code
to keep compiling over and over.
refs: https://github.com/wez/wezterm/discussions/2392
refs: https://github.com/wez/wezterm/issues/1396
Seems that you need to have read everything you want before you
call waitpid, otherwise the pending data seems to be snipped and
prevented from being read.
closes: https://github.com/wez/wezterm/issues/187
