Ref #38 Generate pip package from travis for releasing

[kkazmierczyk]

Fixes #38

This pull requests causes publishing a new pip release.

In order to test it, change the following lines:

deploy:
 - provider: script
   script: python -m twine upload --skip-existing --verbose --password $TWINE_TEST_TOKEN --repository testpypi dist/* #test instance
   # script: python -m twine upload --skip-existing --verbose --password $TWINE_PROD_TOKEN dist/* #production instance.
   on:
     all_branches: true # uncomment for testing purposes
     # branch: prod # uncomment on production
     tags: true # We need to consider if we want to publish all versions or every build (which should not be an issue

I would suggest merging all these changes as one commit.

Then create a new tag e.g. 2.1rc6 and push the tag. The new release on https://test.pypi.org/project/javacore-analyser/#history should appear.