Added a 'special' test for benchmarking

It prints out the mean and standard deviation for tag detection
on ~100 runs.
Remove marker unwrapping

Instead, project sampling points directly in the
original image.

Execution time divided by ~3
Updated 'Refine' to be run at the image level

Instead of the Quad level. This allow to run Refine before decoding
markers. This is especially useful with the new version of
ReadBits that project samples points into the image: precise
localization of the markers enhance the decoding accuracy.