Collisions

[Keywarn]

Now implemented pushing other players out the way. Currently, each car calculates locally who should lose the collision and if they believe they have lost they apply forces based on where the other car is.

• Haven't actually tested this over the network and hoping it can be tested at some point this week, just wanted to create the PR so you can see it and it is ready for Friday once tested.

• The amount of 'pushback' can be changed easily using the collisionAmplifier variable in the VehicleDriverclass. I have left it at a reasonable number but this can only really be decided on after some testing.

Resolves #165 Resolves #164 Resolves #166

[Keywarn]

Hopefully, a bit more to your taste @liamdalg, should make the collisions much better and added a threshold based on car mass.

I've re-requested review but won't merge this stuff until it gets tested.

[ChrisGora]

Me and Riley will test now. Fingers crossed 👍🏼