[Bug-apl] akt feedback

[David B. Lamkins]

Thanks, Blake.

Having to disable the terminal's alt-key menu access is expected. I'll
add that to the README.

(Funny story: I briefly added alt-key access to aplwrap's top-level
menus. I quickly realized my mistake...)

Having to type an extra character (not necessarily a CR) is required to
detect that the pipe is broken. That's already documented. (There
doesn't appear to be a portable way to detect a broken pipe without
attempting a write.)

Thanks for the errata regarding the key map. I'll resolve those as soon
as I have a few free moments.

One more thing to be mindful of: `akt` currently has no way to send a
kill signal to apl, so it won't be possible to interrupt a long
computation. I think I might be able to resolve this by grovelling
through parts of the /proc fs. That might take a bit more time for me to
resolve. Meanwhile, don't do anything that'll require interruption... ;)