Fixed the A2300Update.cpp and A2300RxToFile.cpp fopen calls, which were not specifying 'b' binary mode.  This causes problems in some operating systems like windows as it may encounter a premature end of file.

Added more checking and debug messages for the A2300Update.  Tested release and debug versions multiple times looks solid under windows.  Needs final test on Linux/Apple for high confidence.

Added more documentation, and a readme file for building with visual studio.  A visual studio solution is provided for Windows developers.