Remove incompatible Unicode compatibility types.

As well intentioned as these were, uint16_t and C++11's char16_t are
_not_ actually compatible. They are not implicitly convertible, and
they mangle differently, so they are not even ABI compatible. In our
now wonderous world of C++11, no one should be using these, so just
kill them.

Bug: 18300613
Change-Id: I06d92d7f1d937dd94a620874323d4c50eb6a31bd
Merge "Remove incompatible Unicode compatibility types."
toybox has md5sum, so lose toolbox's md5.

We've now removed enough that for the first time toolbox has
dipped below toybox in size:

  -rwxr-xr-x root     shell      230800 2014-12-11 18:55 toolbox
  -rwxr-xr-x root     shell      233632 2014-12-11 18:32 toybox

Change-Id: I6b150f195dd9f803ddce58a89aa7c23a5b930e5b
Merge "toybox has md5sum, so lose toolbox's md5."