fixes most of the python2 unit tests

2 jobs for master in 1 minute and 35 seconds (queued for 1 second)
Status Job ID Name Coverage
  Test
failed #39857
Linux
test-2.7

00:01:35

passed #39856
Linux
test-3.5

00:01:34

 
Name Stage Failure
failed
test-2.7 Test There is an unknown failure, please try again
  File "/local-hdd/gitlab-runner/builds-1/db2a6fb6/1/adielen/openmesh-python/tests/test_trimesh_normal_calculations.py", line 81, in test_calc_vertex_normal_fast
self.assertTrue(np.allclose(n, np.array([1, 2, 0])))
AssertionError: False is not true

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Ran 110 tests in 0.367s

FAILED (failures=1)
ERROR: Job failed: exit status 1