#4 Add regex support for record- or field-identification

[Anonymous]

It would be really useful to be able to specify a regular expression pattern in the XML file when identifying records. In my case, the first three characters of both the header and footer lines contain a three-character alphabetic code, along with other markers. However, because these characters vary depending on the data file in question, I cannot come up with a field-ident element to positively match these header and footer lines. And no, I cannot use line length because the header and footer are coincidentally identical in length.