Due to the left-handed traffic feature, some GTA2 algorithms broke, such
as spawning ambulances, firetrucks and teleporting hitmen propely.
Firetrucks still can spawn naturally on the streets, but very rarely.

Therefore some missions had to be changed to create a workaround for
these issues.

Missions changed:

- Downtown: Get Gama Rei!
Problem: naturally spawned ambulances become almost impossible to happen.
Fix: Now a ambulance will spawn on the city, driving around. You don't
have to steal it if you somehow got an ambulance before. It's up to you
whether you want to steal the ambulance or try to naturally spawn one.

- Residential: Greatest Hits
Problem: assassins not teleporting near the player
Fix: Now all assassins will spawn already in a z-type. They will teleport
to the player without issues. OBS: because of this change, they will 
appear more frequently, so be careful! Their arrows won't be cleared 
from the screen as they go out of screen because if one of them get lost, 
the player will be able to trace back to them.

- Residential: Fire Truck Fun

Problem: there are limited parked firetrucks and they spawn very rarely when
a car is on fire.
Fix: There will always a second parked firetruck near Camps army base that 
is spawned every time the mission is started.

- Industrial: Hot Dog Homicide
Problem: Some bus stops will not work properly (such as the Azeri Heights one),
because the bus will spawn at the wrong direction, and then moving away from 
the player and getting despawned. But it's still possible to get buses in
other stops, for example at Krishna near the yellow phones, or the zaibatsu
bus stop at front of the kill frenzy tank.

Workaround: don't use the Azeri Heights bus stop for search a bus, 
it definitively don't work. Some other bus stops are harder to spot a bus
depending on the player position/camera, but the Krishna one is the better.
I can't spawn a parked bus because it won't work for getting passengers, 
it must be a naturally generated one.

- Industrial: Sunbeam Contract
Problem: the same of "Greatest Hits".
Fix: Now the second and the third hitmans will firstly enter a buick and
then pursue the player. The first hitman will spawn in a buick.

- Industrial: Karma Assassins
Problem: the same of "Greatest Hits".

- Industrial: Lock Out
Problem: the same of "Greatest Hits", however, in this case it doesn't 
break the mission.

- Industrial: Tanks A Lot
Problem: some tanks may not turn and get stuck in the street corner.
There is no fix for this, but it don't implies that the mission 
will be easier.

- All end missions
Problem: the same of "Greatest Hits"
Warning: all the gang bosses will appear simultaneously, so be careful.
