Add flexible search to CuratorPanel

[amywestlake]

My suggestion for extra flexibility when searching for media.

Currently when an image name includes hyphens or underscores, the image is not returned in search when spaces are used.

This change means searching for ‘my image’ will now return my-image.png.

[awcodes]

Thanks for the PR. Will address it soon. Just doing some research to see if there's and performance implications of having n+1 wildcards in a query.