Four Player Adapter improvements (#608)

* Four Player Adapter improvements
- Corrections and more detail about packet timing and RATE setting
- Clarify meaning and timing of "reply" (a value loaded into SB for tx during the next transfer)
- Add start transmission and ping restart indicators
- Clarification about which consoles can trigger phase switches
- Adapter power info

* Apply suggestions from code review (grammar / punctuation)

Co-authored-by: Rangi <[email protected]>

* Apply suggestions from code review (missed in batch)

Co-authored-by: Antonio Vivace <[email protected]>

* Add Clock Control section, mention and link ping restart sequence

* Fix typoe (duplicated word)

* Change lists at top of charts to sentences and trailing note

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Co-authored-by: Rangi <[email protected]>
Co-authored-by: Antonio Vivace <[email protected]>

Author: 3 people