Moving sha2test js into its own file

This snippet will be easy to paste into whatever.
small refactor, reduce some duplicated code
Use a callback to handle displaying support status

This will let everyone use this script to show whatever messaging
they like. Neato!
Refactor

Remove some duplicated functionality and make things a little easier
on the eyes. We're just about there!
Clean up

- Rename variables and functions for consistency
- Remove some unused variable declarations
- Change function declaration style
- Change public API method name
Return true/false for support callback

This is easier to work with than supported/notsupported. I don't like
boolean function parameters, but I think this is a good use case.
Rename some things to match the domain we're grabbing
Add a license and some boilerplate
Removing some unused files
Updating links to reflect new repo ownership
Adding a bunch of words and making it pretty!
Copy updates
Actually do a SHA-2 test on this page!