Update of windows makefile. Ooops

git-svn-id: https://geany.svn.sourceforge.net/svnroot/geany/trunk@1945 ea778897-0a13-0410-b9d1-a72fbfd435f5

plugins/makefile.win32

@@ -44,7 +44,8 @@ plugins: \
 		htmlchars.dll \
 		demoplugin.dll \
 		classbuilder.dll \
-		export.dll
+		export.dll \
+		svndiff.dll
 
 clean:
 	-$(RM) deps.mak *.o *.dll