Remote whitespace at the ends of lines. Remove blank lines from the ends of files. Change modes on source files so that they are not executable. Signed-off-by: Dan Cross <cross@gajendra.net>

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.