Add PointAtParameter method for Surfaces

[radumg]

Further to the improvements requested in #56 , at @designtechIO we've identified we need the following additional geometric types/operation :

Surface.PointAtParameter - used as a way to create a grid of points across either a surface, polygon or 2d bounding box.

Further notes on this from @ikeough that we (@radumg @markthorley) agree with :

planar surfaces will have their origin at the first vertex of the polygon that bounds the face, with the parameter space “covering” the bounding polygon. But remember that all points at parameter are not necessarily “inside” the surface. So an additional check will be required whether a point IsInside

[MarkThorley]

Current workaround at the moment is to take a polygon, build a bounding box and rebuild the u and v lines from that. Then use PointAt across those curves and translate the points to get a grid. Works fine for the time being so maybe not urgent