[release] fedmsg: 0.16.1

[Ralph Bean]

Hello all,

I've cut a new release of the core fedmsg library with a minor API addition --
a new fedmsg.meta.msg2agent username that we'll use later on in fedora-hubs.

0.16.1
------

Pull Requests

- (@vivekanand1101) Added links to doc in Readme `#352
  https://github.com/fedora-infra/fedmsg/pull/352`_
- (@ralphbean)      Add a new msg2agent API call to fedmsg.meta. `#353
  https://github.com/fedora-infra/fedmsg/pull/353`_

Commits

- Update README.rst `9f394994c
  https://github.com/fedora-infra/fedmsg/commit/9f394994c`_
- Added link to doc in Readme #2 `9b046afc8
  https://github.com/fedora-infra/fedmsg/commit/9b046afc8`_
- Added link to doc in Readme #3 `857264af3
  https://github.com/fedora-infra/fedmsg/commit/857264af3`_
- Add a new msg2agent API call to fedmsg.meta. `a06d6f987
  https://github.com/fedora-infra/fedmsg/commit/a06d6f987`_
- Change test framework to allow testing None values. `69be0e960
  https://github.com/fedora-infra/fedmsg/commit/69be0e960`_
- Add agent tests for the handful of baked-in processors. `bc5d7cb89
  https://github.com/fedora-infra/fedmsg/commit/bc5d7cb89`_
- Some reprs for the UnspecifiedType. `b77448a12
  https://github.com/fedora-infra/fedmsg/commit/b77448a12`_
- Remove header from changelog file. `39a38b61f
  https://github.com/fedora-infra/fedmsg/commit/39a38b61f`_