Fix a few malformed pack and unpack links from experimental.

doc/Language/experimental.pod6

@@ -22,7 +22,7 @@ L<Perl's pack|http://perldoc.perl.org/functions/pack.html>.
 The C<pack> order creates a
 C<Buf> by packing data structures in a certain way given by a I<packing string>
 with the options shown
-L<in the description of C<unpack>\/type/Blob#method_unpack>. You turn it on by
+L<in the description of C<unpack>|/type/Blob#method_unpack>. You turn it on by
 inserting this pragma at the beginning of your program:
 
     use experimental :pack;
@@ -45,8 +45,8 @@ say $buf.unpack("H*"); # OUTPUT: «414243␤»
 Not all of the symbols above are guaranteed to be implemented, and the roadmap
 does not include a fixed date for getting out of that stage.
 
-Please see also documentation for L<C<pack>\/type/Blob#sub_pack> and
-L<C<unpack>\/type/Blob#method_unpack> in the C<Blob> page.
+Please see also documentation for L<C<pack>|/type/Blob#sub_pack> and
+L<C<unpack>|/type/Blob#method_unpack> in the C<Blob> page.
 
 =head2 X<B<macros>|macros>