Re: [relax-ng] Java-style Unicode escapes

> Perl uses \x{N}, so we might want to consider that instead of \u{N}.

Two reasons why one might prefer \x to \u:

1. XML uses "x" to introduce hex char refs.

2. If we use \u, people may be surprised that it it is followed by an 
argument in braces rather than 4 hex digits as in Java.

James