update trovesource to match repository getTrovesByLeaves behavior.  Also add ability to override bestFlavor and getleaves for findTroves for trovesources.
update trovesource to match repository getTrovesByLeaves behavior.  Also add
ability to override bestFlavor and getleaves for findTroves for trovesources.


fedora-conary/conary,fedora-conary/conary,fedora-conary/conary,fedora-conary/conary,fedora-conary/conary