This modifies the behavior of the '-e' flag to PCbuild\build.bat: when '-e'
is not supplied, no attempt will be made to build extension modules that
require external libraries, even if the external libraries are present.
Also adds '--no-<module>' flags to PCbuild\build.bat, where '<module>' is
one of 'ssl', 'tkinter', or 'bsddb', to allow skipping just those modules
(if '-e' is given).
The old project files move to PC/VS9.0 and remain supported.
VS2008 is still required to build 2.7; VS2010 (or later, plus Windows SDK 7.1)
is *also* required to use the new project files.
Zachary Ware