es_98

[edwery]

I think this covers the required changes.

There are other cases which I have ignored:

1) 'status' is used as a $_GET query parameter in class_u3a_admin - I think thats a correct use of the reserved word.

'cat' is used as a value of a query parameter in some places - but thats fine, its the name of the parameter which cannot be a reserved word.

This change will have backward compatibility issues for anyone who has created these lists already, either as a shortcode or generated using the editor and attributes. This is because the display parameters as grabbed from either $atts or $_GET, but use the same parameter names, so I could not change the $_GET parameter names without changing the javascript which reads the attributes too.

[edwery]

I confirmed that I could reproduce the problem with main, and not with es_98

[edwery]

I have added backwards compatibility so older blocks should still work if the newer parameter names are missing