Myfaces 2.2.8 release artifacts

[Mike Kienenberger]

It's in no way a show-stopper, but we should deal with the .asc.md5
and .asc.sha1 artifacts generated at some point.

Udo wrote that one solution is to upgrade to Maven 3.3.1.  See
http://jira.codehaus.org/browse/MNG-5504 for details.