[4.0] Adding Lerp function in the math helper

[Pandav0x]

Purpose of this PR

This PR aims to add the linear interpolation (LERP) function in the MathHelper class. (Closes #892)

Testing status

Tests haven't been written yet.

[Perksey]

Also you don't need to write tests at this stage.

[Pandav0x]

Should I add an ArgumentOutOfRangeException if t is less than 0 or greater than 1 ?

[Perksey]

That's probably best given that this is the imprecise method.

[varon]

Just to chip in here:
Throwing an exception at runtime stops this from being a total function. It's probably better to just clamp t to [0;1].

Automatic clamping is very convenient. Unity's Mathf.Lerp function operates this way as well.

[Pandav0x]

Thank you very much, I've clamped t to [0;1] instead of throwing an error.

[Perksey]

If that's all, remove the WIP mark and I'll merge :)

[Pandav0x]

Thank you :)

[varon]

Thanks @Pandav0x .

Every little bit counts. Well done, and we hope to see loads more in the future!