Update version.

I wonder if there's a way to fix this Makefile to be slightly less
totally unreliable.
diff --git a/Demo/embed/Makefile b/Demo/embed/Makefile
index c8d538b..ac935f1 100644
--- a/Demo/embed/Makefile
+++ b/Demo/embed/Makefile
@@ -10,7 +10,7 @@
 srcdir=		../..
 
 # Python version
-VERSION=	2.3
+VERSION=	2.5
 
 # Compiler flags
 OPT=		-g