This patch replaces the old sockets with a new, random type.
Spline sampling is a very necessary feature for any data. Entering
a spline index is important because users most often perceive
them as isolated objects and global interpolation was considered
a strange solution that had several problems:
Accuracy on large curves.
Difficulty finding offsets. ...
And also, the global nature of the input length used to make it
impossible to transfer data cyclically for closed curves.