FIX: compatibility with 32bit arches

[kotopesutility]

For 32bit arches error occurs:

Traceback (most recent call last):
File "", line 189, in _run_module_as_main
File "", line 148, in _get_module_details
File "", line 112, in _get_module_details
File "/usr/src/VNEV/lib/python3/site-packages/mdp/init.py", line 131, in
from . import utils
File "/usr/src/VNEV/lib/python3/site-packages/mdp/utils/init.py", line 6, in
from .routines import (timediff, refcast, scast, rotate, random_rot,
File "/usr/src/VNEV/lib/python3/site-packages/mdp/utils/routines.py", line 295, in
_UNSAFE_DTYPES = [numx.dtype(d).type for d in
^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/usr/src/VNEV/lib/python3/site-packages/mdp/utils/routines.py", line 295, in
_UNSAFE_DTYPES = [numx.dtype(d).type for d in
^^^^^^^^^^^^^
TypeError: data type 'float128' not understood

This pull request fixes this bug.

[Stewori]

Thank you for this fix! Looks good, I'll accept it right away.