Bodge some fixes for the VS project.

This probably doesn't actually compile, but it's less wrong than it was
beforehand.
Do a round of clang-format.
Fix typo in config.sh.
There can be only one sed.
Autofy some things that could be autofied.
Use std::size_t.

Believe it or not, clang-modernize (and possibly some other tools) understand
std::size_t, but not size_t, when <cstddef> is concerned.
Simplify AudioSink construction.

No more AudioSinkConfigurator.  No more tears.

I've started moving playd to C++14 here.  This may be controversial, but the
main reason (make_unique) is supported by VS2013 as well as sufficiently modern
gcc/clang.
make_unique<>ify this->io.
Change internal device IDs from strings to ints.

This eliminates a round-trip of conversion to/from strings.
Change sample rate to uint32_t.

No need this being floating-point now every single audio source provides an
integral sample rate.
errors: Remove shadowing parameter.
Reform responses.

There is now a Response class, which has responsibility over building and
escaping responses.  These features have now moved out of ResponseSource, whose
days may very well be numbered.

ResponseSink now takes Responses wholesale; RespondArgs is gone.