Added a version of blend that takes a float argument so that two colors may be blended at a ratio other than 50-50.
Added a version of blend that takes a float argument so that
two colors may be blended at a ratio other than 50-50.


git-svn-id: a1a4b28b82a3276cc491891159dd9963a0a72fae@1593 542714f4-19e9-0310-aa3c-eee0fc999fb1

threerings/narya,threerings/narya,threerings/narya,threerings/narya,threerings/narya