Tag and release 3.0.0-beta1 next week

[Tom Zeller]

As discussed on the call today, the plan is to tag and release
OpenSAML and the IdP as 3.0.0-beta1 next week. Given the holiday,
aiming for Tuesday Nov 25 seems to make sense but we might slide into
Wednesday Nov 26.

Early next week I'll bump dependency versions as well as Maven plugins.

I imagine java-support, spring-extensions, and parent-v3 will be bumped as well.