make sure that the ttransaction_info contains only packages that have the transacts bit set

can happen if transaction_create_decisionq is called with a decisionq
that doesn't match the pool's obsolete flags.
rename selection_make_deps to selection_make_matchdeps, add marker support

Also add pool_intersect_evrs.
add solv_memdup and solv_memdup2 inline helper functions
add solver_rule2rules: learnt rule introspection