The option positioning.ss-similarity introduced in this commit allows to
chose the desired algorithm to compare two measurements. One can chose
between the historical mean euclidean distance algorithm and the new
algorithm using the number of values within the interval
[mean-std.dev.;mean+std.dev.].
The returned distance is now "averaged" to take into account the number
of measurements in the lists. The former behaviour would lead two
couples of measurement lists with a different number of measurement to
have non-comparable distances.
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.