Tokenize the option "Group multiple values"

Problem

Today the options under "Group multiple values" can only take static values. This works in most cases, but when building complex views this isn't always sufficient.

Solution

If we can have the options "Show n values" and "Starting from n" tokenized those values would be able to use other fields' values. This would allow for more dynamic views without any big impact on CCK's codebase or the performance of the view. This also plays nice with the new Views integration in content_multigroup.module for 6.x-3.x when using the [delta] token for fields in a multigroup.

The attached patch works and applies to both 6.x-3.x and 6.x-2.x as content_handler_field_multiple.inc hasn't changed. The patch will still need some documentation as well as modification to options_form() in order to present all the available tokens in a sensible way.

This patch is sponsored by LRF Media and will be maintained and rerolled by NodeOne.