This is the companion setting to canUpload, letting you control whether existing files from the asset store can be referenced. It's particularly useful when using UploadField on the front-end.
The field carries the configuration, and some non-upload functionality
like "attach files" still relies on the fileupload jQuery plugin
being initialized.
Conflicts:
templates/UploadField.ss
Fixed the calculation of height for the upload (non AssetUploads) area
so that the save button would show. Took off the min-height, as this
will cause UI issues when there are multiple files open for editing.
