retire: seam-conversation, seam-parent, seam-solder, openjpa

[gil]

Hi,
I want retire: seam-conversation, seam-parent, seam-solder
I do not have many reasons to keep them still
And if someone can take care of openjpa package or can give a help as 
co-maintainer.
https://issues.apache.org/jira/browse/OPENJPA-2386
Unusable and not buildable with Java8. As last resort I will have to 
pick up too, and the
packages that require it.

regards
- gil