DnT Ancient City Overhaul

# Ancient City Overhaul v3.4 #
 -  fixed some houses, statues and pillars not showing up before
 - Gave main walls (the wool path walls) generation priority over smaller structures
 - Changed chance of smaller houses to have a 70% chance to have a chest
 - Ancient Cities are now rarer:
   - before 1 would spawn in a 24x24 chunk field with at least 8 chunks between 2 cities, that lead to them sometimes merging together
   - now 1 spawns still in a 24x24 field but there are now at least 20 chunks between 2 instances of them, effectively preventing them from merging together but also making them rarer since deep darks are quite small
 - Loot table changes for the overhauled loot table:
   - rolls now 2-4 times for generic loot
   - swift sneak was removed from generic loot and moved to treasure loot
   - LV 2 Regeneration potion has been removed from generic loot and moved to treasure loot
   -  LV 2 Regeneration potion only can apear in a group of 1 and not 1-4 anymore (no more potion spam)  - The Main Walls uper wall area has been trimmed down to be like vanilla since it was a leftover and just spawning ground for unfair shriekers
 - The Main Walls path directly beside them is now 5 blocks wide instead of 3
 - small paths are still 3 blocks wide but are now made up out of deepslate tiles
 - Changed how suspicious gravel generates. instead of capped processor it now uses a chance based processor due to MC-308792
   - this means as example: instead of 5 gravel with generic loot and 1 gravel with treasure its now 5% and 1%. not optimal but nothing i can fix about it. take that up with mojang