Clarify the status of GEN (Unknown) sources

[martindholmes]

One item in the sources list consists of the id "GEN" and the gloss "(Unknown)". There are 1028 links to this item, in 989 different trader records. Here is a collection of example records that have three or more such links:

https://hcmc.uvic.ca/project/bbti/collection.html?collTitle=Records%20with%20many%20links%20to%20GEN%20source&records=124036;122074;50459;95983;65347;122107

In many of these cases, a clear source is given in a note, so the link to "Unknown" is, on the face of it, erroneous. It seems to me that the pattern of assigning this source to a record, then adding a note with a true source in it, is mostly undertaken when the source is a text which is unlikely to be generally cited in other records, and therefore perhaps does not merit inclusion in the formal list of sources on the sources page.

However, the resulting record appears a little confusing, so I wonder if we might address these cases by perhaps adding another pseudo-source whose gloss/description better explains the situation, and reserving "Unknown" for cases where the source genuinely is unknown. Also, there may be some cases where a source does merit adding to the main sources list, and could then be re-linked in the conventional way.

[DavidJamesShaw]

Yes, these 'GEN (unknown)' notes look quite confusing.
If it is possible to make some improvement, I can't see any objection.