#15 xreflabel should be fully supported

[Noah Slater]

As an example:

If you link or xref to an anchor element there is no way to override the text that is output for the hyperlink which derives it's value from the anchor's id.

Having the hypertext read "(See [appendix-a.bridgehead-0], page 34)" is not very user friendly. Docbook2x should support the xreflabel attribute.