Due to references being stored in the context as weak references (in order to avoid things on a .FORGET object from triggering unconstructed references) the references in the BONUS tokens that need to check for "old" skills cannot be thrown away.
This "permanently" stores the references.

Issue#: CODE-2528


git-svn-id: svn+ssh://svn.code.sf.net/p/pcgen/code/Trunk@23648 ef53c05b-3124-4d59-ae7d-fe3273f42be7