pause when current best is a backtrack, fixes #201

src/main/java/baritone/pathing/movement/movements/MovementTraverse.java

@@ -319,6 +319,14 @@ public class MovementTraverse extends Movement {
         }
     }
 
+    @Override
+    public boolean safeToCancel(MovementState state) {
+        // if we're in the process of breaking blocks before walking forwards
+        // or if this isn't a sneak place (the block is already there)
+        // then it's safe to cancel this
+        return state.getStatus() != MovementState.MovementStatus.RUNNING || MovementHelper.canWalkOn(dest.down());
+    }
+
     @Override
     protected boolean prepared(MovementState state) {
         if (playerFeet().equals(src) || playerFeet().equals(src.down())) {