Normalise a set of Frame coordinates representing one point astNorm
For some classes of Frame, whose coordinate values are not constrained, this function will never modify the values supplied. However, for Frames whose axes represent cyclic quantities (such as angles or positions on the sky), coordinates will typically be wrapped into an appropriate standard range, such as zero to 2pi.
The NormMap class is a Mapping which can be used to normalise a set of points using the astNorm function of a specified Frame.
It is intended to be possible to put any set of coordinates into a form suitable for display by using this function to normalise them, followed by appropriate formatting (using astFormat).