[xliff] Attribute Values - Update

Hi all,

Here is another update for the proposed standard values. I've tried to
consolidate the last emails. Note that some items (the ones marked with **)
refer to a block of values (too time consuming to put them all in the XSD
before we discuss them). They have generaly a URL that leads to the full
list.
Note: the XSLT template has been updated too.

I'm working  hard at the draft 2 for the specification document. Should be
out hopefully today or tomorrow.

cheers,
-yves