Event sub URLS and start of subscribe method

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extra : rebase_source : 20a9e0692da3f1e6a6a4bdd51298d5f8e684c7e5
Event server

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extra : rebase_source : 4a8ccd16f34d423234d206afff45b7e1c80fd1a6
Better docstrings, iter_event_vars, and sids implemented

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extra : rebase_source : 368b7ba4a185d1c9cca210c9193bc73fcd4e41ee
Removing unused class variable

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extra : rebase_source : b97c46d6d891e03f31c1e6e1d3d95423ae0bbcb7
Update __init__.py to include event_queue

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extra : rebase_source : ea09a7b5a038fd4f670d13a7aa1666c6a989a84a
Build and upload wheels
Really removing unused class variable

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extra : rebase_source : a47c4765405d9115868289e8a075298e42659ca8
Allow server socket reuse

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extra : rebase_source : 490987ca260898b77feef9ae9b9ec81597e1cff2
Update README.rst

Fixed typo in first example
Merge pull request #121 from lawrenceakka/eventing

Eventing - you asked for it!
Use requests.structures.CaseInsensitiveDict instead of dict for self.headers.

Python 2.x delivers a mimetools.Message with lowercased keys, Python 3.x
delivers a http.client.HTTPMessage with uppercased keys.
Merge pull request #129 from petteraas/event_headers_uppercase

OK - all done thanks
Setup make lint, added make lint to travis script target.
Added flake8 and pylint as dev requirements.
Added check of ROVI_API_KEY and ROVI_SHARED_SECRET.

 - Only print track-image ( and surrounding markup ) when it's not None.
Return None in 'get_track_image' when r.status_code not ok.
fix pylint complaints
Deprecate soco.SoCo.get_speakers_ip() in favour of soco.discover()
Removed redundant initialize of self.speakers_ip