Allow RSSFeed/XML link by event type to be comma separated if using multiple event types.

when trying to pass “type=#” to view only specific event types on the XML link, you can only do one at a time. I would like the option to comma separate and apply two or more event type IDs rather than have to create separate XML links for each:

&type=1,3

rather than &type=1 and &type=3 in separate links