Import p5-MooX-ClassAttribute-0.011 as devel/p5-MooX-ClassAttribute.

This module adds support for class attributes to Moo. Class attributes are
attributes whose values are not associated with any particular instance of
the class.

For example, the Person class might have a class attribute "binomial_name";
its value "Homo sapiens" is not associated with any particular individual,
but the class as a whole.

(mef)