Add ability to edit a bitstream's filename as well as description, format, etc. in XMLUI's EditBitstream form.
This is a trivial change and helps keep parity with JSPUI. There are implications to renaming bitstreams – none severe, but worth considering.
1. Bitstream links are usually displayed with the filename included.
Since handle and sequence ID are what actually matches the request to the item+bitstream, this is not a problem. Old/cached/indexed links will still work.
For this reason, editing bitstream filename in the EditBitstream form is actually safer than deleting and re-uploading the bitstream, which would generate a new sequence ID and cause old links to be unusable (a lot of repository managers use this as a workaround currently)
2. Bitstreams derived from filter-media processes (eg. THUMBNAIL/image.jpg.jpg and TEXT/document.txt.txt) will, in practice, become orphaned, and on the next filter-media run, the derived bitstreams will be regenerated and added to the TEXT, THUMBNAIL. etc. bundles. This is potentially a problem, in terms of storage space, search term boosting, thumbnail duplication could affect display of item lists, and so on.
Attaching patch that's tested internally at my institution, but will not commit until vote at dev meeting has been taken and others have had a chance to comment.