added new program: remanence_anisotropy.py
added new program: remanence_anisotropy.py

this new program combines aarm_magic.py and atrm_magic.py. In the
future airm_magic.py could be also added here if someone needs it.
Added alteration check to ATRM.

Caoimhinmg/PmagPy,lfairchild/PmagPy,Caoimhinmg/PmagPy,lfairchild/PmagPy,lfairchild/PmagPy,Caoimhinmg/PmagPy