Replacing binsizex with multi2 version

src/comm.cpp

@@ -248,6 +248,7 @@ void Comm::init()
   // Could remove NP_NEWTON from npair_full_*multi2*, but could be cryptic
   // Also could be cases where you want newton off (hybrid) but don't use multi2 comm
   // Could add check on neighbor build, if full and comm->multi2 error...
+  // or just add check on comm setup - is that run before every run? Only if box change...
   if (force->newton == 0 && multi2)
     error->all(FLERR,"Cannot use multi2 communication with Newton off");
 }