graying out vocabulary results in the picker that match but are unacceptable

We could just remove unacceptable items from the vocabulary results, but that would confuse users who think the picker is broken when the search doesn't find what they are looking for. The picker normally just retrieves a batch of five items from the vocabulary. It would be easy to have the IPickerEntry adapters to add some additional data that would get passed back to the picker. Currently the c.l.browser.vocabulary.HugeVocabularyJSONView only accepts arguments for the vocabulary name and the search text. It would be necessary to add an optional argument that would indicate which filter should be applied.