Add permission for Moondial and unrecognized SFX

[Arthri]

• Added explicit cases for cases 2, 4, and 5 of Packet 51. These are harmless and so are approved with no checks
• Added a handler for case 6 or Enchanted Moondial of Packet 51. Added a new permission, tshock.world.time.usemoondial, to regulate Enchanted Moondial's use
• Added a default case for Packet 51 which instead checks for the tshock.specialeffects.{type} permission if TShock does not recognize the case yet

[Arthri]

Fixing DisableDungeonGuardian requires a non-trivial amount of work, so I've decided not to do it in this PR. The Dungeon Guardian is spawned by the server, deep inside the NPC.SpawnNPC method, which would require IL patching and all the strings attached with that