Groovy blogs relocation

Hi folks,

The ASF infra team is encouraging folks to move away from the old roller
blogging system.

Groovy has moved our blog content into our website. You can find it here:

https://groovy.apache.org/blog/

All the old content should redirect automatically to the new system but do
let us know if you spot any glitches.

The new system uses Asciidoc like the rest of the Groovy website. The good
news is, it is now even easier for any folks in the Groovy ecosystem to add
content!

Simply create a PR for the groovy-website repo in the blog folder:

https://github.com/apache/groovy-website/tree/asf-site/site/src/site/blog

Have a look at the other Asciidoc files (.adoc) in that folder to see the
format.

You might want to also send an email to the dev list if you think any
discussion is needed.

Also, there is a preliminary atom feed file at the following location:

https://groovy.apache.org/blog/feed.atom

Please give us feedback if the current format doesn't suit your needs.

Cheers, Paul.