Chronological bookmarks, PB+SWMH fix for realm_decisions

- Bookmarks are now chronological
  - The *The Old Gods* and the *Stamford Bridge* bookmark texts are prefixed with a short note indicating that *William the Conqueror* is the preferred, balanced bookmark
  - The *War of the Two Eriks* was removed
  - The *William the Conqueror* bookmark text indicates that is the preferred, balanced bookmark
- PB+SWMH no longer fails to parse ````realm_decisions.txt````
- Changelog now also reflects claimant faction CB fix