Fix zed stuck at water tunnel.

Adjust some ambient.

2019/11/26 HotFix :

Reduce total orbs from 106 to 80.

Pacman Mission 1 requires 30 (50 formerly)

Pacman Mission 2 requires 70 (106 formerly)

And change some Orb's location, make it easier to find.

2019/11/25 Changelog:

1. Renew all lightmap of mesh entirely.
2. New ammo crate looking.

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3. Adjust ammo crate's respawn delay :

A - In endless mode, delay will increase every wave.
B - If your server has more than 7 players, ammo crate's delay will change.

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4. New Objective Mode!

Total 11 waves, every wave use custom style objective.

Note: this one still has burning dispenser, however the damage reduce to 4.

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5, In survival mode, one wave will encounter a random objective mode. (Endless spawning zed objective)