Master fix muon track steering tools
This is MR 1 of many (I suspect). I think I have fixed most of the immediate problems with MooTrackBuilder and MooTrackFitter (and I have added ATLAS_CHECK_FILE_THREAD_SAFETY just to these two).
I took the opportunity to migrate both to the new Gaudi property declaration style, and ran a comparison with q221 output from the nightly to try to make sure that I didn't introduce any errors.
Edited by Edward Moyse