Moved the snapToBase() utility function to region.*pp

I've also adjusted the TODO file, which really shouldn't be committed.
Still, it's there now, so it stays. I don't think the logger is going to
be possible any time soon, so I'll probably look into the disconnection
handler.

common/map/region_pager_base.cpp

@@ -21,8 +21,6 @@
 */
 #include "region_pager_base.hpp"
 
-#include "utility.hpp"
-
 #include <stdexcept>
 #include <algorithm>