#160 Artist sorted by-alpha creating erroneous inbetween separators in the sort list

`<staging:8080>/artist/sorted/by-alpha` `Artist` list sorted `by-alpha` displays erroneous `inbetween` separator title for sort groups. e.g. Blannk inbetween separators and out of sort order separators such as `F` after `H` again. I would like... * The `artist` sorted `by-alpha` list to display the correct inbetween sort separator for the respective title sort order.

See examples below