pyIRSF-2.1 released

The main change is that sigma clipping using M.A.D.(median absolute deviation) is adopted for median sky bias frame construction. You can choose the conventional IRAF's sigclip+mclip median combine as well in sirius.param/sirpol.param.

pyIRSFmanual160212J.pdf and pyIRSFmanual160212E.pdf are also released.