Building SDCC with Borland C++ under Windows

1: Build SDCC under Cygwin as documented in cygwininst.txt (this is
necessary in order to run all the necessary configuration steps).

2: From the sdcc directory, run the command "make -f Makefile.bcc". This
should regenerate all the .exe files in the bin directory except for
sdcdb.exe (which currently doesn't build under Borland C++).

3: If you modify any source files and need to rebuild, be aware that the
dependancies may not be correctly calculated. The safest option is to
delete all .obj files and run the build again. From a Cygwin BASH
prompt, this can easily be done with the commmand:

 'find . -name "*.obj" -print | xargs rm'

from the sdcc directory.