Test fail on newest python2x and numpy.

[adamist521]

Tested on Python 2.7.9 , Numpy 1.9.2.
13/90 test failed probably due to small unequality of number.

One example which failed.

FAIL: testsample (__main__.MultiNormalDistributionTests)
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Traceback (most recent call last):
  File "/usr/local/Cellar/python/2.7.9/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/pymix/tests/mixtureunittests.py", line 524, in testsample
    self.assertEqual(str(s), '[-1.3330318465269027, 1.2010161194550606, 0.35547714589258694]')
AssertionError: '[-1.3330318465269027, 1.2010161194550606, 0.35547714589258717]' != '[-1.3330318465269027, 1.2010161194550606, 0.35547714589258694]'
----------------------------------------------------------------------

Also I had to change importing

import mixture

to

from pymix import mixture

cause I installed from pypi.