absolute URLS in references

[davidgil]

in skill.md at least in mysql it uses links to github repo, has no sense for local dev

[bddicken]

This was a purposeful decision to make it easier for people to get the latest updates, without having to remember to re-download the skill regularly. We hope that these can evolve over time, especially early after launch as we refine these. They are a great start, but can certainly be improved with more use and input.