Improved hashCode implementations for the Vector classes.

Block[World]Vector was ignoring changes of y < 128 (i.e. all of them) and changes of x < 8192.

src/main/java/com/sk89q/worldedit/BlockVector.java

@@ -93,8 +93,8 @@ public class BlockVector extends Vector {
      */
     @Override
     public int hashCode() {
-        return (Integer.valueOf((int)x).hashCode() >> 13) ^
-               (Integer.valueOf((int)y).hashCode() >> 7) ^
+        return (Integer.valueOf((int)x).hashCode() << 19) ^
+               (Integer.valueOf((int)y).hashCode() << 12) ^
                 Integer.valueOf((int)z).hashCode();
     }
 }

src/main/java/com/sk89q/worldedit/BlockWorldVector.java

@@ -126,8 +126,8 @@ public class BlockWorldVector extends WorldVector {
      */
     @Override
     public int hashCode() {
-        return (Integer.valueOf((int)x).hashCode() >> 13) ^
-               (Integer.valueOf((int)y).hashCode() >> 7) ^
+        return (Integer.valueOf((int)x).hashCode() << 19) ^
+               (Integer.valueOf((int)y).hashCode() << 12) ^
                 Integer.valueOf((int)z).hashCode();
     }
 }

src/main/java/com/sk89q/worldedit/Vector.java

@@ -585,9 +585,12 @@ public class Vector {
      */
     @Override
     public int hashCode() {
-        return ((new Double(x)).hashCode() >> 13) ^
-                ((new Double(y)).hashCode() >> 7) ^
-                (new Double(z)).hashCode();
+        int hash = 7;
+
+        hash = 79 * hash + (int) (Double.doubleToLongBits(this.x) ^ (Double.doubleToLongBits(this.x) >>> 32));
+        hash = 79 * hash + (int) (Double.doubleToLongBits(this.y) ^ (Double.doubleToLongBits(this.y) >>> 32));
+        hash = 79 * hash + (int) (Double.doubleToLongBits(this.z) ^ (Double.doubleToLongBits(this.z) >>> 32));
+        return hash;
     }
 
     /**