1. adds new option that reverts old way of comparing checksums which is required for my old P2DX
2. enables this driver on QNX Neutrino
3. fixes small stupid errors
4. solves one of regressions listed in 2791151 bug (sonar readings). Problem is not easy: the bug is in robot_params.h file which, according to remarked comments is automatically generated by saphconv.tcl from Saphira parameter files. The RangeConvFactor field used by sonars is of int type while the value that should be set for P2DX is 0.268 which results in zero being stored in the structure. As a result, all sonar readings are multiplied by zero, so there's no readings at all. In the erratic driver the same robot_params.h file has the same field, but this time it is of double type. My patch sets this to double for p2os too. It is possible that other *Conv* fields must also be changed to double for p2os, as it is done in robot_params.h for erratic.
Still there's a problem with gripper. I'll try to fix it as soon as I'll have it physically back here.