Generate 2D points by successively turning and stepping.
AnglePath[{θ 1, θ 2, θ 3, …}]
AnglePath[{{r1, θ 1}, {r2, θ 2}, {r3, θ 3}, …}]
AnglePath[θ 0, {step1, step2, …}]
AnglePath[{x, y}, {step1, step2, …}]
AnglePath[{{x, y}, θ 0}, {step1, step2, …}]
AnglePath[{{x, y}, {dx, dy}}, {step1, step2, …}]
AnglePath[init, steps, form]
AnglePath[{}]
→ {{0, 0}}