Optimise all the things

[TrueCP6]

• [x] AbsoluteValue
• [x] Add
• [x] And
• [x] AngleBetweenVectors
• [x] AngleDifference
• [x] ArccosineInDegrees
• [x] ArccosineInRadians
• [x] ArcsineInDegrees
• [x] ArcsineInRadians
• [x] ArctangentInDegrees
• [x] ArctangentInRadians
• [x] Compare
• [x] CosineFromDegrees
• [x] CosineFromRadians
• [x] CrossProduct
• [x] DirectionFromAngles
• [x] DirectionTowards
• [x] DistanceBetween
• [x] Divide
• [x] DotProduct
• [x] HorizontalAngleFromDirection
• [x] Max
• [x] Min
• [x] Modulo
• [x] Multiply
• [x] Normalize
• [x] Not
• [x] Or
• [x] RaiseToPower
• [x] RoundToInteger
• [x] SineFromDegrees
• [x] SineFromRadians
• [x] SquareRoot
• [x] Subtract
• [x] TangentFromDegrees
• [x] TangentFromRadians
• [x] VectorTowards
• [x] VerticalAngleFromDirection
• [x] XOf
• [x] YOf
• [x] ZOf

Thanks to @Zezombye for a lot of the optimisations.

To do:

• [x] Allow EqualsTo to work with Elements, Variables and Enums
• [x] Constant support for Up, Down, Left, Right, Forward, Backward

Stuff that could be done but would be a pain and wouldn't be that useful:

• ArrayContains
• ArraySlice
• CountOf
• FilteredArray
• FirstOf
• IsTrueForAll
• IsTrueForAny
• LastOf
• IndexOfArrayValue
• RemoveFromArray
• SortedArray
• ValueInArray

[Zezombye]

Careful though :

• Checking if things are equal must take into account the random() functions
• The boolean operators do short-circuiting, so true && 3 must return 3 and not true

[TrueCP6]

Does the short-circuiting only happen with number constants or can it happen with a variable or other elements?

[Zezombye]

Everything, like in JS.

[TrueCP6]

Ready for review