Review and fix all the tests so that 100% of the tests pass.
There are still many compilation warning and many tests fail, but at least everything builds.
Stop using Boost for unordered_set, unordered_map and hashes.
To be consistent with the other modules, the positioning server must be called OwlPS Positioner instead of Positioning, and the executable owlps-positionerd (even if the daemon mode is not implemented yet). That's a big commit for a tiny change.