Support some features when using PolledUpdate

[Yoooi0]

• Auto-home
• Speed limit, it has to either limit value range, or has to have longer move duration than from script (those options might be the same?) #179
• Maybe possible to support looping script/custom curve motion providers #173
• Maybe possible to support random motion provider by sampling opensimplex at low and slightly random rate

The snapshot needs to be changed from From/To Keyframe to TargetValue+Duration