#53 Implement the dyn:map() EXSLT function

[Eric van der Vlist]

This function would be most useful in Schematron:
unlike XSLT, Schematron has no support for loops and
dyn:map() would introduce this support in XPath.

Use cases for this feature include those recently
described on xml-dev:

http://lists.xml.org/archives/xml-dev/200609/msg00010.html

and

http://lists.xml.org/archives/xml-dev/200609/msg00012.html

Thanks,

Eric