Class storage of a point for an OdDgDimension.

The dimension string (point list) describes the baseline of the dimension. In other words, each point sets the reference point for each witness line. The points are not necessarily collinear, and their position in the list determines their usage, according to the type of tool that was used to create them. 

For angularAxis, radial, and diameter dimensions, the first point is a center point. 

The second point always seems to set the dimension shaft position, using the OffsetToDimLine, from which all other witness lines lengths may be calculated. 

Corresponding C++ library: TG_Db