[TLA] Keep area activated during cinematics

Problem

During a cinematic, the player switch to SPECTATOR gamemode.

1. As a spectator, the ArmorStands that displays components are visibles.
2. Because there is no player having a non spectator gamemode in the area, the area is deactivated (and unloaded) ?

Note: Activate areas having a spectator inside is not the solution because:

• In some case the spectator exists the area during the cinematic.
• We still want to be able to switch gamemode to reset an area.

Solution

1. ArmorStand visible during cinematic

We will simply delete the armorstand texture in the resource pack. Joran did it. We will just have to check the result.

2. Area deactivated during cinematic

We will add a feature allowing to keep an area loaded and activated.

This will be done using 2 commands (with area id/location):

/le area keepActivated <area_id>

/le area keepActivatedLoc <any location in the area> <world name>

/le area stopKeepActivated <area_id>

/le area stopKeepActivated <any location in the area> <world name>

And the same will be accessible using 2 BQ events (see InventorySaveEvent for a sample event implementation).