Re-add _text_ filter options for _uuid_ columns

As mentioned in #144 I did run into a situations where _text_ filter options are useful for _uuid_ columns.
These should not be the default and performance is not the primary concern here.

I think these can be implemented as:

- begins with `$column >= overlay('00000000000000000000000000000000' placing $term from 1)::uuid AND $column <= overlay('ffffffffffffffffffffffffffffffff' placing $term from 1)::uuid`
- ends with `replace($column::text, '-', '') LIKE '%$term'`
- contains`replace($column::text, '-', '') LIKE '%$term%'`

Assuming `$term` is pre-normalised something like `regexp_replace($term, '[^0-9a-f]+', '', 'g')`.

Start by locating the existing filter handling for UUID columns and review the related discussion in issue #144. Re-add begins-with, ends-with, and contains options without making them defaults, and verify that the generated queries normalize terms as described.

Written by the indexing model from the issue text.