Following optimisations now utilising multicore better on OS X.

9000 solutions per second at 70 square.
1000+ solutions per second at 256 square.
280 solutions per second at 512 square.
60+ solutions per second at 1024 square.

Also add precision to solver timings as at least for 70 square was
running out of significant digits.
Set the build to unchecked and the size to 512 for fastest sensible results.
Merge branch 'basicOptimisations'