Added TileInjectionRules' tilesets into the list returned by GetTiles(this DungeonFlow dungeonFlow)

[WhiteSpike]

• Changed GetTiles(this DungeonFlow dungeonFlow) implementation to include the tilesets present in the dungeon flow's TileInjectionRules instances.

What issues does this pull request aim to solve?

• Fix issue Network prefabs are not registered for objects spawned within injected tiles #145
  • Tomb 0.2.7 was used to test this scenario. The apparatus would not spawn for clients other than the host. With the change proposed in this pull request, all present clients can see the apparatus in question.