[split] Browse by Composer

[guermantes]

An option to set which tag is used to populate the first Tag view column could be doable but which tags are on the table and which one's make sense?

So far its only Genre or Composer.

From my own perspective those two would suffice! :-) 

Would it be doable to have an additional choice in the Library dropdown, say between Tag and Album, that leads to the same view as Tag but with the Tag panel populated by composers? 

Or make the Genres panel header clickable in order to toggle between genre and composer?