Ensure hdf5.h is included before netcdf.h to avoid build error with openmpi >= 1.4.1

--- libsrc4/nc4internal.h
+++ libsrc4/nc4internal.h
@@ -8,13 +8,13 @@
 
 #include <config.h>
 #include <stdio.h>
+#include <hdf5.h>
 #include "error.h"
 #include <stdlib.h>
 #include <ctype.h>
 #include <stdarg.h>
 #include <string.h>
 #include "netcdf3.h"
-#include <hdf5.h>
 #include <netcdf.h>
 
 #ifdef USE_PARALLEL
--- libncdap4/ncdap4.h
+++ libncdap4/ncdap4.h
@@ -12,9 +12,9 @@
 #include <stdio.h>
 
 #include "config.h"
+#include "nc4internal.h"
 #include "netcdf.h"
 #include "nc.h"
-#include "nc4internal.h"
 #include "ncdap.h"
 #include "getvara.h"
 #include "constraints3.h"