Merge remote-tracking branch \'toybox/master\' into HEAD

Merge remote-tracking branch \'toybox/master\' into HEAD
am: a898e9c

* commit 'a898e9c4b457765173a0ec6adea26d45b70b744c': (34 commits)
  Fix build when wchar_t is unsigned.
  Fix exit code of things like sed -i that use tempfile_handler().
  basename: fix segfault on null input; add tests
  Add od -w.
  toolbox prlimit is no more.
  Debian bug 635570 did something horribly nonstandard (depending on a side effect of "sed -e 'a\'" with no trailing line). But there's an actual user, and it's not hard to implement, and it's not hard to implement, and there isn't an obvious _other_ way to do it, so add the behavior and a test for it.
  Fix bzcat.test (as noted by Andy Chu), wean tests off $TOPDIR and supply $FILES instead, move tests/blkid into tests/files/blkid.
  The test infrastructure prints the command name now, so file.test shouldn't.
  Minor blkid cleanup. (There was a while(ptr[-1]==' ') ptr--; that could fall off the start of the string. I pulled on the thread...)
  Redo build stuff in response to Andy Chu's suggestions.
  blkid: Handle short/empty vfat labels; update tests
  Posix requires "" to be false, and 00 should be false, and -0 should be false. Fix memory leaks in regex. Simplify regex check (if we matched, subexpression had to match). Don't exit() from a command, set exitval and return.
  Make lsof 10x faster by caching /proc/net socket info.
  Fix last commit (had newline before first ==> name <==) and add -f tests.
  Fix "tail -f single_file".
  expr cleanup: simplify get_str() and free returned allocations.
  Remove 'exit' from xargs test too.
  Fix bug where all tests aren't being run with 'make test'.
  expr cleanup: traverse optargs with tok instead of incrementing optargs and copying itinto a second variable. Also add error message for empty ( )
  Move whitespace and curly brackets around, move reference URLs to top of file, eliminate syntax_error() function (just call error_exit() directly), eliminate advance() wrapper, pipe expected error messages in test to /dev/null
  ...

Change-Id: I59e775d702b1930dff37e8b0736857f6cbb4a6b6