[Image-SIG] Windows CRT issues with Python 2.6

[Koen van de Sande]

To check for the manifest, I just open it up in a hex editor and look 
for the word "manifest". That will get you to the XML part of the file, 
and you can see what's happening.
Please note that if you turn manifests off, you assume that your 
extension has no other dependencies. And for things like TCL/TK, Windows 
Common Controls, there can be additional dependencies in the XML file. 
So, only remove the dependency on the runtimes, otherwise you break 
things with additional dependencies.

Koen