[XSLT 2.0] limits on numbering sequences

Comment on: 12.3, first paragraph after the bulleted list:

There are numbering sequences whose intrinsic limit is less than 1000.
For example, the formatting token ① (circled digit one) has
a limit of 20 imposed by the Unicode character repertoire.
Thus the second last sentence in the paragraph needs to be changed to
read:

 For the numbering sequences described above,
 any upper bound imposed by the implementation must not be
 less than 1000 (one thousand).

to make it clear that it is any IMPLEMENTATION imposed limit that may not
be less than 1000.