[AD] SCons Configure() bug fixed

[Jon Rafkind <workmin@xxxxxxxxxx>]

This was just posted to the SCons dev list about the Configure bug 
currently existing in scons 0.96.1:

We use the sconscript_reading value as a hint about when a Configure
context is being applied.  The sconscript_reading value was being used
as a semaphore, when it really should be a counter.

Thanks to Jon for the patch (and including the sample SConscript files
demonstrating the bug).  The patch had to be modified slightly to match
namespace reorganization in the Script/*.py modules.

       --SK

The SCons people seem to have a pretty formal process so Im not sure 
when this will actually go into cvs or whatever or even when a new build 
of scons will come out but a new version comes out it will surely have 
this fix.