#27 Add reflection based deep-sorting to all "Selectable" lists.

[Jürgen Kellerer]

Currently there's no good sorting capability for lists that hold hierarchical data like "$class.fields" or "$select.classesBelowPackage".

If would be great to sort these lists using constructs like:

$sortedFields = $class.fields.sort("name")

or

$sortedFields = $class.fields.sort("annotations.@XmlAttribute.name", "annotations.@XmlElement.name")