Remove actual mapQ calculation temporarily
Remove actual mapQ calculation temporarily

We are spending the vast majority of our time doing float operations,
the results of which don't actually make any difference at the moment,
so disabling this for now till we can find a good solution.

benedictpaten/cactus,benedictpaten/cactus,benedictpaten/cactus,benedictpaten/cactus,benedictpaten/cactus