Enhance code review process with Travis CI

[dmvass]

Hello @myarik!

Can you please add travis ci integration for this repo. I have already created travis ci configuration file in the root and tested it with fork. I hope it's very improve our code review process.

Best regards.

[myarik]

Hi, @kandziu

I added the Travis ci integration but looks like one test is not passed

[dmvass]

@myarik can you give me a link to the failed test please?

[myarik]

tests/test_filters.py ......................................             [ 30%]
tests/test_mixins.py .......                                             [ 36%]
tests/test_pagination.py ........                                        [ 42%]
tests/test_serializers.py ........                                       [ 48%]
tests/test_validators.py ..............................................  [ 85%]
tests/test_views.py .............F....                                   [100%]
=================================== FAILURES ===================================
________ TestElasticAPIView.test_filter_search[query_params3-expected3] ________
tests/test_views.py:151: in test_filter_search
    assert sorted(result) == sorted(expected)
E   assert [2, 5, 6, 8, 10, 12] == [2, 6, 8, 10]
E     At index 1 diff: 5 != 6
E     Left contains more items, first extra item: 10
E     Use -v to get the full diff
===================== 1 failed, 124 passed in 8.37 seconds =====================
ERROR: InvocationError for command '/home/travis/build/myarik/django-rest-elasticsearch/.tox/drf34-py27-dj108-esdsl5/bin/python setup.py test' (exited with code 1)