Adds documentation for object equality

It's actually another example of the documentation already in the eqv description. Anyway, closes #2004

Author: JJ

doc/Language/objects.pod6

@@ -83,6 +83,24 @@ and assign to the container it returned with the L<C<=>|/routine/=> operator.
 All objects support methods from class L<Mu|/type/Mu>, which is the type
 hierarchy root. All objects derive from C<Mu>.
 
+Object equality needs a specific operator:
+L<C<eqv>|/language/operators#infix_eqv>, the structural comparison
+operator:
+
+=for code
+class Foo {
+    has $.bar;
+    has $.baz
+};
+my $bar = "42";
+my $baz = 24;
+my $zipi = Foo.new( :$baz, :$bar);
+my $zape = Foo.new( :$bar, :$baz);
+say $zipi eqv $zape; # OUTPUT: «True␤»
+
+Object identity, on the other hand, uses C<===>. Using it above will return
+C<False>, for instance.
+
 X<|Type objects>
 =head2 Type objects