remove dead links, separate HISTORY section

There are some dead links and the Revision history section make entire README hard to read.

Since @emamirazavi set up a new package on PyPI, his repository should be linked.

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A few additional things;

1. Please turn on Issues if you are serious about maintaining python3-ping, which I believe you are, or you wouldn't bother to create new package on PyPI. Since python-ping looks dead to me, so it'd be nice that you can take bug reports.
2. Please edit the repository's Website URL on top of page. Which is still linked to ``https://github.com/jedie/python-ping``, a very dead link.
3. I remove `maintainer_email` from `setup.py` because I don't know @emamirazavi's email address.