Packaging improvements

[mikebryant]

• Use versioneer, so releasing will end up being as simple as tagging a version
• Releases may be done by tagging the repo (e.g. use the Github UI), and will automatically be deployed to Pypi

[bhs]

@mikebryant thanks! Have you tested this yet?

[mikebryant]

@bhs yup, I ran this on my fork with appropriate changes against test.pypi.org and it worked. (and this is the same basic model we use for our public python packages)

[bhs]

Sounds great! I think you should merge this. LGTM. (I'll let you manage the merging process at your discretion)

[mikebryant]

Hmm. I don't seem to have access to accept merge requests?

[bhs]

@mikebryant your invite is pending: https://github.com/opentracing-contrib/python-django/invitations

[mikebryant]

Oh derp, I missed the email notification. Thanks! :)