Table Normalization

Hello,

Out of a slightly different requirement Andrew Welch sent a very good XSL stylesheet which handles "normalization" of a table using colspan and rowspan attributes into a table where each row has the same number of cells.

I just put in some finishing touches, comments, and removed code which was related to the original requirement. 

Imagine the following table (using table, tbody, tr, and td elements width colspan and rowpsan attributes):