while here also delete the two remaining makefiles from before the -portable merge.

fixes `make distcheck'. it's so GNU to not ship manpages by default :/

since we may want to spawn other programs, mark every file descriptor as cloexec. Fortunately, we don't end up opening many of them!

The `page' command fetches a file and displays it using less(1). To do this, refactor fetch_fid to accept a file descriptor and add a spawn utility function.

when a tailq is proprerly initialized, there's no need to check if it's empty and insert in head position.

Drop the IMSG_AUTH_DIR imsg type and stuff everything in a struct kd_auth_proc that gets sent via IMSG_AUTH. Tweak the necessary bits to compile. While here also start documenting what data we send over which imsg. As an added benefit, now we're sending fixed-size messages instead of variable length strings.

the debugger is already disabled by some lisp tricks, so it's redundant. Moreover, we need a way to optionally toggle the debugger, so hardcoding the flag isn't useful at all.