* Update onbuild instructions
Hi,
I'm guessing there's a fair chance that the venn diagram of sentry users and docker users doesn't have too much overlap. I've updated the onbuild image documentation to help people get started with a little more information.
I hope you find my additions to the readme helpful.
Thanks.
* doc: Remove README changes
They'll move to content.md
* doc: Move changes in README to onbuild docs
* style: fix markdownfmt warnings
* style: fix markdownfmt warnings again