Fixes those programs on Windows.

MSDN documentation suggests always passing this flag to reduce
overhead for an "obsolete technology".

None of the current FormatHResultError() callers need the format string.

Parameters should better be captured.  This removes some complexity
from Async().

Closes https://github.com/MusicPlayerDaemon/MPD/issues/1102

Stop early, don't try more formats if it is clear that we have no
chance.

Fixes assertion failure in the Thread destructor.

Fixes crash due to std::stoul() throwing std::invalid_argument.

Reduce header dependencies.

Reduce header dependencies.

Reduce header dependencies.