Moved IDL_array_indices.py to IDL2py_conversions directory.
Moved IDL_bytscl.py to IDL2py_conversions directory.
Moved IDL_hist_equal.py to IDL2py_conversions directory.
Moved IDL_histogram.py to IDL2py_conversions directory.
Moved unit_test_IDL_Hist.py to IDL2py_conversions directory.
Moved unit_test_IDL_hist_equal.py to IDL2py_conversions directory.