Loosen language in 6.d deprecation warnings

- .path talks about Rakudo specifically; toss versions, since
    we won't actually be able to emit those warnings
- Pair.freeze: remove version from message. Deprecation was deferred
    to 6.e and I don't think the proposal has had enough eyes yet
    to guarantee removal will occur.

Author: zoffixznet

doc/Type/Cool.pod6

@@ -672,8 +672,8 @@ Defined as:
     method path()
 
 B<DEPRECATED>. I<Existed only in the Rakudo implementation and isn't part of
-any language released. Issues deprecation warnings in 6.d language and will be
-removed  entirely when 6.e language is released.>
+any language released. Will issue deprecation warnings in future language
+versions and eventually will be removed entirely.>
 
 Stringifies the invocant and converts it to L<IO::Path> object.
 Use the L«C<.IO method>|/routine/IO» instead.

doc/Type/Pair.pod6

@@ -301,7 +301,8 @@ Makes the I<value> of the C<Pair> read-only, by removing it from its L<Scalar co
     CATCH { default { put .^name, ': ', .Str } };
     # OUTPUT: «X::Assignment::RO: Cannot modify an immutable Str (apple)␤»
 
-B<NOTE:> this method is proposed for removal in B<6.d> language and its use is not recommended.
+B<NOTE:> this method is proposed for removal in future language versions and its
+use is not recommended.
 
 =head2 method Str