Unlock parent POM?

[Tom Zeller]

> But in this specific case, we bumped Spring, so I think we want to unlock
> the parent?

Uh, yes, I guess consider not doing so an error on my part after
bumping the Spring (and to some extent Jetty) versions.

I'll bump spring-extensions and idp-parent. But I assume I should not
bump opensaml-parent or java-support, since they don't depend on
Spring nor Jetty, is that correct ?