std: remove the equals method from TotalEq.

`TotalEq` is now just an assertion about the `Eq` impl of a
type (i.e. `==` is a total equality if a type implements `TotalEq`) so
the extra method is just confusing.

Also, a new method magically appeared as a hack to allow deriving to
assert that the contents of a struct/enum are also TotalEq, because the
deriving infrastructure makes it very hard to do anything but create a
trait method. (You didn't hear about this horrible work-around from me
:(.)

src/libstd/reference.rs

@@ -54,8 +54,4 @@ impl<'a, T: TotalOrd> TotalOrd for &'a T {
 }
 
 #[cfg(not(test))]
-impl<'a, T: TotalEq> TotalEq for &'a T {
-    #[inline]
-    fn equals(&self, other: & &'a T) -> bool { (**self).equals(*other) }
-}
-
+impl<'a, T: TotalEq> TotalEq for &'a T {}