xslt and math

Hi,

My first comment is that math support is poor to non-existent
in XSLT and should be incorporated directly in the
language rather than forcing the user to use java
or other extension functions.

Another comment I have is that the support for rounding
provides only the limited and un-common default mode
of round-half-to-even.  While this may be theoretically 
sound, it isn't practical and forces us to use java extension
functions.

Apart from this, everything is great.