Removed bytewise_impl.cpp
Version 1.8.2.3

+ Now using interface decomposition: IProtocol + IOProvider.
  IProtocol implementation receives IOProvider instance, performs some actions with it via interface,
  then receives incoming data via signal callbacks;
+ AsioImpl, AsioMTImpl, BlockwiseImpl changed according to aforementioned policy;
+ Most Win32 specific code moved to blockwise_impl.cpp;
+ dllmain.cpp now utilizes timeBeginPeriod/timeEndPeriod from winmm.lib;