Automatically fetch node's current title if an internal link title is empty

It would be a usability/functionality enhancement if links to internal nodes could automatically pull in the title of a node rather than a saved value in the database. This prevents stale link titles and inconsistency. The idea is that this functionality would be automatic if a link to a node is not given a title. To implement this a few changes are needed:

1) Change link forms so that blank titles are allowed if a link is to an internal node.
2) Upon rendering links, if a link does not have a title and it is a link to an internal node then grab the current title of that node on the fly.
3) An update function to remove titles from links to internal nodes where the title is the same as the link itself.

The attached patch is a current snapshot of work in progress from a co-worker. Further work and documentation is needed. Comments on the approach and the desire for this functionality in the links module would be appreciated. Personally I think this functionality makes a lot of sense.