Document room:Update()

[Zamiell]

In the docs, it says that room:Update() is useless, but it isn't useless.

• Take the case of spawning a trapdoor where a pit already exists.
• If you simply remove the pit and try to spawn a trapdoor, the pit will be successfully removed, but the trapdoor will not appear.
• The solution is to remove the pit, call room:Update(), and then spawn the trapdoor.

Thus, I think that the docs should recommend that it is best practice to always call room:Update() after removing any grid entity. This recommendation should appear on both the section for room:Update() and room:RemoveGridEntity().

Separately, please link to this issue in the documentation for room:Update().

[wofsauge]

Updated infos in 7dc6909