Provide a faster way to get a location. Adds BUKKIT-3120

Currently when a plugin wants to get the location of something it calls
getLocation() which returns a new Location object. In some scenarios this
can cause enough object creation/destruction churn to be a significant
overhead. For this cases we add a method that updates a provided Location
object so there is no object creation done. This allows well written code
to work on several locations with only a single Location object getting
created.

Providing a more efficient way to set a location was also looked at but
the current solution is the fastest we can provide. You are not required
to create a new Location object every time you want to set something's
location so, with proper design, you can set locations with only a single
Location object being created.

src/main/java/org/bukkit/craftbukkit/block/CraftBlock.java

@@ -48,6 +48,19 @@ public class CraftBlock implements Block {
         return new Location(getWorld(), x, y, z);
     }
 
+    public Location getLocation(Location loc) {
+        if (loc != null) {
+            loc.setWorld(getWorld());
+            loc.setX(x);
+            loc.setY(y);
+            loc.setZ(z);
+            loc.setYaw(0);
+            loc.setPitch(0);
+        }
+
+        return loc;
+    }
+
     public BlockVector getVector() {
         return new BlockVector(x, y, z);
     }