more cleanup of #include files. common.h is the only file allowed to include system .h files unprotected by autoconf HAVE_ symbols. define.h is the only other file allowed to include system .h files. define.h is never installed; common.h is installed if we are building the shared library.

--- a/src/common.h	Mon Feb 02 21:55:48 2009 -0800
+++ b/src/common.h	Tue Feb 03 10:59:10 2009 -0800
@@ -2,6 +2,12 @@
 #ifndef __COMMON_H
 #define __COMMON_H
 
+
+#ifdef HAVE_CONFIG_H
+    #include "config.h"
+#endif
+
+
 #include <stdlib.h>
 #include <stdio.h>
 #include <stdarg.h>