wip

WARN: emscripten.h added, too late?
REMOVE more debugs
Stockfish command line NodeJS-based runner
Asynchronous input processing
Customizable UCI output mechanism

Instead of writing it to cout, collect whole output in string stream and
emit it with overridable handler.
wip
Disable some platform-specific behaviours

Depending on target platform or compiler, several optimizations
(including raw assembly language) could be inserted.  Disable them.
fu makefile
Print debug output to proper stream

Sync_cout no longer uses std::cout so that needed to be updated.
Problematic line removed from benchmark

Synchronous wait removed instead of reworking it.  Benchmark may be
broken now.