Create latest release page for 0.28.0

[doveye]

To do:

• [ ] Add OpenJDK support statements (which versions does this release support)
• [ ] Pick one or 2 high value changes from What's new
• [ ] Find out what performance changes should be included
• [ ] Find out if there are any other specific things to highlight for this release
• [ ] Link to the correct version topic in the user doc for more information

See previous issue, #294, for an example.

[pshipton]

This was done via https://github.com/eclipse-openj9/openj9-website/pull/301