Totem Name Plates

- Battlegrounds and arenas: enemy totem nameplates are no longer handled there, as they don't work in those places. The addon leaves the nameplates alone, which also saves the work.
- The Battlegrounds tab now only holds "Hide enemy totem names beyond nameplate range", set apart from the World one: the addon switches the game setting as you enter or leave a battleground or arena.
- The tooltip of this option names the game setting it changes: the CVar UnitNameEnemyTotemName (0 when ticked, 1 when not).