link style in docs: github vs yard

[ConorSheehan1]

I just came accross this issue on yard lsegal/yard#1017
Basically github requires this style of link [changelog](CHANGELOG.md) but yard requires this {file:CHANGELOG.md}

I changed the links in the readme to work on github in pr #53
Now the link works in the github readme, but it's broken in the docs on rubygems.
If you go to the readme on rubygems and follow the link to the changelog, you'll get a not found error for changes.md

Do you think the fix provided in the issue would make sense for spira?
Or should we choose between github or yard style links?

[gkellogg]

Documentation should live on rubydoc.info as it does for other ruby-rdf projects, but the README doesn't show this.

In general, IMHO, we should optimize for yard, and point there from the README. I'll update the README with a section on this.

[ConorSheehan1]

Makes sense to me, I'll revert that link