Yeenaghu level redesign

[TommiGustafsson-HMP]

• [x] No ghouls, replace all with thouls, can be a lot of them
• [x] Several "barracks" rooms full of flinds and flind lords
• [x] Throne room with a throne, Yeenaghu and a big number of body guards (flinds, flind lords, and thouls)
• [x] Yeenaghu summons thouls, a lot of them, not ghouls
• [x] Some decorations, such as artwork and carpets
• [ ] Some bookshelfs (?) and more chests
• [x] Yeenaghu should not wander off his place to attack the player

[janne-hmp]

Done.