Pluggable Version and Milestone Sorter

[Carsten Klein <carsten.klein@…>]

The current version and milestone sorting is rather generic.

However, it fails on correctly sorting versions such as 1.0.0proto_stable and 1.0.0proto_alpha, 1.0.0alpha_stable, 1.0.0beta_proto.

These, at least in my world, should be sorted as follows

1.0.0proto_alpha 1.0.0proto_stable 1.0.0alpha_stable 1.0.0beta_stable

The same is true for milestones implementing a similar naming scheme.

What I propose is to allow the user to plug-in both sorters for milestones and versions and make this available as extension points, with the default behaviour being either hard coded into the existing components or externalized as default implementations of these interface.

I already did some work on this and the existing system seems to work, but will fail on input that does not match the sorter's production scheme, i.e. it will raise an exception thus preventing lists from being displayed. So additional work must be invested.

In addition, these sorters should also be able to reverse sort the input based on an additional parameter.