Move libfmt, libutf into subdirectories of lib9. Add poll-based socket i/o to libthread, so that we can avoid using multiple procs when possible, thus removing dependence on crappy pthreads implementations. Convert samterm, acme to the single-proc libthread. Bring libcomplete, acme up-to-date w.r.t. Plan 9 distribution.

Until I hear otherwise, Refs aren't used enough to merit their own assembly. They are now implemented with locks.

Will we ever finish?

Silence a few more warnings. Strip down the mkfiles more. Fix bug in X11 mouse handling, note groups.

the .C files compile but are renamed to avoid building automatically.