* part 2 of the initial doc fixes
- spelling fixes
- grammar fixes
- em-dashes should be em-dashes (`—`): double dashes (`--`) are not rendered properly
- reduce overusage of em-dashes, some of those should be separate sentences
- use the correct syntax for notes, tips and warnings
- every sentence is in a separate line (helps with future diffs)
- add missing dots at the end of list items
- fix some lists
* sentences on separate lines in the remaining files
* add doppelganger detection explanation to FAQ and link to Joe's guide from our Pi guide
* Edit CLI options page
* cp
* merge with ith unstable
* prysm migration guide: add steps until import slashing db
* update systemd
* update troubleshooting
* update pi guide
* metrics: replace winners with community
* update migration guide
* cp
* progress with guides, various edits