"New project" catalog search form always omits non-text materials

[srjfoo]

The catalog search used to pre-fill the metadata for a new project has a checkbox, checked by default, to omit non-textual materials. While this is almost certainly what we want for DP, there's really not any sense in having a checkbox if you can't get results that include the non-textual material.

That is, you can uncheck the box, do a search, and that search omits non-textual materials, if you refine search, when you get back to the form, the checkbox is checked again.

I'm pretty sure that this worked at one point, but I don't know if it should be fixed so that it works, or just assume that all non-textual materials should be omitted.