Use AnimationCurve (customisable cubic Hermite splines) rather than the wrapper FXCurve (probably Catmull-Rom?)

[eggrobin]

Echoes from IRC:

<Sesquipedalianovy> S nicks Best nicks
<Sarbian> Superiors Nick !
== egg|debugging has changed nick to Seggrobin
<...>
<Seggrobin> So FXCurve is a wrapper for AnimationCurve that removes the ability to customise tangents...
<Seggrobin> Why, SQUAD, why... :'(
* Seggrobin bangs his head against his keyboard dhgdhf7b
<Sarbian> nothing stop me from using AnimationCurve instead for smoke screen. it just make the config a bit more complex
<Seggrobin> Sarbian: It would be a *good* idea. It's more powerful (and you can make the tangents optional, just as they are in AnimationCurve)
<Seggrobin> Then we'll have cubic Hermitian splines to work with, at least *that* makes sense
<Sarbian> Drop me a pm so I don't forget it. Time to sleep, I'll have a long day of fun with Heartbleed related subject at work tomoorw