* Update to spec v0.9.0
* Update to v0.9.1
* Bump spec tags for v0.9.1
* Formatting, fix CI failures
* Resolve accidental KeyPair merge conflict
* Document new BeaconState functions
* Fix incorrect cache drops in `advance_caches`
* Update fork choice for v0.9.1
* Clean up some FIXMEs
* Fix a few docs/logs