Update ex 047 comment and patch

exercises/047_methods.zig

@@ -88,7 +88,7 @@ pub fn main() void {
         // Loop through every alien...
         for (aliens) |*alien| {
 
-            // *** Zap the Alien Here! ***
+            // *** Zap the alien with the heat ray here! ***
             ???.zap(???);
 
             // If the alien's health is still above 0, it's still alive.

patches/patches/047_methods.patch

@@ -1,4 +1,4 @@
-87c87
-<             ???.zap(heat_ray_strength);
+92c92
+<             ???.zap(???);
 ---
->             alien.zap(heat_ray_strength);
+>             heat_ray.zap(alien);