Default to CNAbility when possible to use
(pushes use in prepration for using CNAbility as the "Choose Driver" [and thus source of associations] when an Ability is involved)

Issue#: CODE-2465


git-svn-id: svn+ssh://svn.code.sf.net/p/pcgen/code/Trunk@23414 ef53c05b-3124-4d59-ae7d-fe3273f42be7