Add M309, plus additional missing parameters

Adds some missing code and parameters to documentation, plus M309.md There are also some fixes to values/types in which were originally wrong or redundant. - Added some links to `Requires LCD controller` or `EEPROM` or whatever documentation calls for. - Renamed `Set and/or get` or `Get or set` to `Set / report` (bulk of files that were changed, I know not a big deal, but it corresponds to what was done in the Marlin repo). - Unsure what `eeprom: true` did, removing it and testing didn't seem to have made a difference. ### Ease of use - I grouped these commits as best I can so if you wanted to look through/cherry pick or revert its a bit easier.