tests/sixtracklib/opencl: Port existing tracking unit-test to NS(ClContextBase_*) API
tests/sixtracklib/opencl: Port existing tracking unit-test to NS(ClContextBase_*) API

- Remove all explicit OpenCL parts of the unit-test and rewrite based on the
  NS(ClContext) and NS(ClContextBase) API -> explicit includes of OpenCL
  headers are no longer required!!!

- Abstract the inner loop over the available nodes into a helper function to save on
  repetitions -> this function should also work for BeamBeam related functions!!!!

SixTrack/SixTrackLib,SixTrack/SixTrackLib,SixTrack/SixTrackLib,SixTrack/SixTrackLib