Fix for issue #2573: Can't change the framework name on OS X builds

This introduces a new configure option: --with-framework-name=NAME
(defaulting to 'Python'). This allows you to install several copies
of the Python framework with different names (such as a normal build
and a debug build).
diff --git a/Mac/BuildScript/resources/ReadMe.txt b/Mac/BuildScript/resources/ReadMe.txt
index 1a6e637..cb00c93 100644
--- a/Mac/BuildScript/resources/ReadMe.txt
+++ b/Mac/BuildScript/resources/ReadMe.txt
@@ -19,7 +19,7 @@
 extension modules that open up specific Macintosh technologies 
 to Python programs (Carbon, AppleScript, Quicktime, more).
 
-The installer puts the applications in "MacPython $VERSION" 
+The installer puts the applications in "Python $VERSION" 
 in your Applications folder, command-line tools in
 /usr/local/bin and the underlying machinery in
 $PYTHONFRAMEWORKINSTALLDIR.