#4 Build fix for GCC 3.4.2

[Anonymous]

Apparently, grid.cc missing #include <math.h>, since it
uses floor(), and thus does not build in its vanilla
form. This is a quick fix:
%%%
--- grid.cc.orig Wed Sep 15 16:21:00 2004
+++ grid.cc Wed Sep 15 16:21:47 2004
@@ -15,6 +15,7 @@
// Copyright Liam Girdwood 2003

+#include <math.h>
#include "grid.hh"

namespace Vega

%%%
by danfe@nsu.ru