Experimental upgrade for v2.2.0

[LWisteria]

#33 trial cupy/cupy@v2.1.0.1...v2.2.0

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[jenkins-maekawa]

Test (commit 94e35f2) failed on titanv.

============================= test session starts ==============================
platform linux -- Python 3.6.5, pytest-4.3.0, py-1.8.1, pluggy-0.13.1
rootdir: /home/clpy-jenkins-slave/workspace/clpy_testing_titan, inifile: setup.cfg
collected 159 items

test_distributions.py ........                                           [  5%]
test_generator.py ...................................................... [ 38%]
.......................................F...................              [ 76%]
test_permutations.py ....                                                [ 78%]
test_random.py .                                                         [ 79%]
test_sample.py .................................                         [100%]

=================================== FAILURES ===================================
______________________ TestChoiceChi.test_goodness_of_fit ______________________
../../../clpy/testing/condition.py:75: in wrapper
    fail()
../../../clpy/testing/condition.py:52: in fail
    instance.fail(msg)
E   AssertionError: 
E   Fail: 1, Success: 0
E   
E   The first error message:
E   Traceback (most recent call last):
E     File "/home/clpy-jenkins-slave/workspace/clpy_testing_titan/clpy/testing/condition.py", line 61, in <lambda>
E       lambda: f(ins, *args[1:], **kwargs),
E     File "/home/clpy-jenkins-slave/workspace/clpy_testing_titan/tests/clpy_tests/random_tests/test_generator.py", line 410, in test_goodness_of_fit
E       self.assertTrue(hypothesis.chi_square_test(counts, expected))
E   AssertionError: False is not true
==================== 1 failed, 158 passed in 26.93 seconds =====================

[jenkins-maekawa]

Test (commit 94e35f2) failed on vega.

============================= test session starts ==============================
platform linux -- Python 3.6.5, pytest-4.3.0, py-1.8.1, pluggy-0.13.1
rootdir: /home/clpy-jenkins-slave/workspace/clpy_testing_vega, inifile: setup.cfg
collected 159 items

test_distributions.py ........                                           [  5%]
test_generator.py ...................................................... [ 38%]
.......................................F...................              [ 76%]
test_permutations.py ....                                                [ 78%]
test_random.py .                                                         [ 79%]
test_sample.py .................................                         [100%]

=================================== FAILURES ===================================
______________________ TestChoiceChi.test_goodness_of_fit ______________________
../../../clpy/testing/condition.py:75: in wrapper
    fail()
../../../clpy/testing/condition.py:52: in fail
    instance.fail(msg)
E   AssertionError: 
E   Fail: 1, Success: 0
E   
E   The first error message:
E   Traceback (most recent call last):
E     File "/home/clpy-jenkins-slave/workspace/clpy_testing_vega/clpy/testing/condition.py", line 61, in <lambda>
E       lambda: f(ins, *args[1:], **kwargs),
E     File "/home/clpy-jenkins-slave/workspace/clpy_testing_vega/tests/clpy_tests/random_tests/test_generator.py", line 410, in test_goodness_of_fit
E       self.assertTrue(hypothesis.chi_square_test(counts, expected))
E   AssertionError: False is not true
==================== 1 failed, 158 passed in 37.55 seconds =====================