Oops, capitalization in ex016.

exercises/016_for2.zig

@@ -39,5 +39,5 @@ pub fn main() void {
 // As mentioned in the previous exercise, 'for' loops have gained
 // additional flexibility since these early exercises were
 // written. As we'll see in later exercises, the above syntax for
-// capturing the index is part of a more general ability. hang in
+// capturing the index is part of a more general ability. Hang in
 // there!