Add more string substitutions for "join phrase"

When adding more than one artist to a track, one must enter " & " or ", " (with the spaces).

If one adds "," or "&" (no spaces) the Artist field does not render properly (i.e. without spaces).

I am suggesting adding logic so that if the join phrase is entered as "," (no spaces), it is substituted to ", " (with a space).
Also, if the text entered as "&" (no spaces) it is substituted to " & " (with spaces). These are common errors that lead to rejected edits that would be correct otherwise.