A few minor changes to help build on Linux

Still get "PolyVox/include/Volume.inl:128: error: ‘mVolume’ was not declared in this scope" though

include/VolumeIterator.inl

@@ -19,7 +19,7 @@ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 ******************************************************************************/
 #pragma endregion
 
-#include "block.h"
+#include "Block.h"
 #include "Volume.h"
 
 using namespace boost;