Interface of builders which allow to build curve objects by successively adding
Points cannot be added directly to a curve since curve objects are immutable
(cannot be changed at a later time, i.e., after construction).
Instead, a clone with an additional point is created. To efficiently create
a new curve by successively adding points use this builder.
isParameter - A boolean, specifying weather the point should be considered a free parameter (true) or not (false). Fee parameters can be used to create a clone with modified values, see Curve.getCloneForParameter(double)