revision to docs

@gtback @ikiril01 I made a new branch to get around git brain damage on my end

To address your prior comment - I refactored the layout, added a link to RTD, fixed the footer, and changed the 'indicators' wording

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Where did the content come from? I see some correspondence with what's on the wiki, but I feel like a lot of it got lost—and not just the proposals, which we do want to keep on the wiki.
I'd probably just leave most of the python-cybox content off, and instead point to http://cybox.readthedocs.org.
There needs to be some sort of navigation bar, or at least the ability to get back to the homepage by clicking on the page header. I know @johnwunder used Bootstrap for the STIX docs, and it looks pretty nice (though I'd update to Bootstrap 3). I hope it's straightforward to get Jekyll and Bootstrap to play nicely.
A minor thing, but using "Indicators" on the CybOX page is likely to confuse some people (despite the fact that we're talking about IOCs).
A lot of the links go to unexpected (to me, at least) pages. It's not immediately obvious from the home page where to go next.
Nothing mentions MITRE.
Don't use headers (i.e. h4) in the footer :smile: