add a "qplookups" benchmark test

add a "qplookups" benchmark test

this loads a file containing DNS names and measures the time it takes to:
1) iterate it,
2) look up each name with dns_qp_getname()
3) look up each name with dns_qp_findname_ancestor()
4) look up a modified name based on the name, to check performance
   when the name is not found.