* Follow up methods changes on re6stnet registry API.
  * getIPv4Information was simplifed on registry, so reimplement it.
  * Remove scripts generated and keep a single script to orchestate the token management.
  * Drop some code duplication
  * Remove babeld, openvpn and miniupnp as they are not required.
  * Remove useless scripts.
  * Remove re6stnet section, extra-eggs is more them enough and prevent duplications.

When a process is stopped:
- it may not have emitted logs since previous rotation: add "missingok"
  As a direct consequence: stop using logrotate recipe.
- its pid file (if applicable) may be missing: test its non-empty presence
  before calling slapos-kill
Also, stop using slapos.cookbook:logrotate.
Update obvious users (cloudooo, neoppod, erp5, monitor, re6stnet).