Header file clean-up:

1. Remove all.h and PC_HEADER junk.
2. Rolled mem.c and mem.h into imports.c and imports.h
3. Include imports.h instead of mem.h
Restore _mesa_create/initialize_context() to be like they were in 4.0.4
New wrappers for a few std C functions: _mesa_atoi(), _mesa_strstr(), etc.

src/mesa/drivers/x11/xm_tri.c

@@ -1,4 +1,4 @@
-/* $Id: xm_tri.c,v 1.27 2002/08/07 00:45:07 brianp Exp $ */
+/* $Id: xm_tri.c,v 1.28 2002/10/24 23:57:23 brianp Exp $ */
 
 /*
  * Mesa 3-D graphics library
@@ -35,7 +35,7 @@
 #include "glxheader.h"
 #include "depth.h"
 #include "macros.h"
-#include "mem.h"
+#include "imports.h"
 #include "mmath.h"
 #include "mtypes.h"
 #include "xmesaP.h"