Convert mass quadrupole moment samples to h0 in known pulsar pipeline

The known pulsar pipeline can be run so as to generate samples in mass quadrupole (and distance), rather than in h0. However, the results plotting script expects to find h0 samples. So, a modification has been made to convert mass quadrupole (Q22) into h0 when they are read in. The change also converts any distance samples from metres to kpc. This change to the pipeline has been tested and works as expected.

cc @karl-wette