Create possibility for locale teams to "stick a note" on their front page

[tobifjellner]

Please create a possibility for locale teams to create a short message (which may contain one or several links to specific posts/pages under their own Rosetta locale and/or /team or /support sub-site) and display this message in a highlighted area near the top of their main start page.

For instance, the Korean team would use this to invite new contributors to their community team revival project on ​https://ko.wordpress.org/ with a link to the corresponding post/page on their /team site.

This suggestion/request is based on a wonderful idea from @presscat2015