0.1.0-beta5 'Got that holiday feeling'

This is a breaking release, it is NOT backward compatible with 0.1.0-beta4. State files generated by earlier versions must be removed before starting the beta5 daemon.

Breaking changes

• Persist zone fixes and improvements. (#804 by @ximon18)

Bug fixes

• Overhaul how re-signing timers are managed, preventing race conditions causing
  crashes when zones are removed. (#863 by @bal-e, reported in #730 by
  @jpmens)
• Prohibit removing a zone while it is being restored from disk.
  ([#886] by @bal-e)

Other changes

• Speedup zone restore by parallelizing sorting. (#872 by @ximon18)
• Make logging during zone restoration consistent. (#874 by @ximon18)
• Improve memory use of NSEC(3) in incremental signing. (#842 by
  @Philip-NLnetLabs)
• Log the reason when unable to restore zone state on startup. (#878 by
  @ximon18)
• Add metrics for the duration of the last loading and signing operations.
  (#876 by @tertsdiepraam)

Known issues

• Removing a zone whilst it is being signed causes a panic. (#888)
• Removing a zone does not cleanup its persisted state files. (#889)

Acknowledgements

Thanks to @bortzmeyer, @bzwitt, @gryphius and @jpmens for testing Cascade and
providing valuable feedback!