Changed dir name from pmagpy_data_files to data_files
Changed dir name from pmagpy_data_files to data_files

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