section 5.1 PRIORITY frame and idle state clarification

[Scottmitch]

section 5.1 has the following text:

idle:
All streams start in the "idle" state. In this state, no frames
have been exchanged.

It seems like PRIORITY frames can be sent/received in the IDLE state without causing a state transition as illustrated in figure 2. If I am interpreting this correctly then the no frames have been exchanged statement is not necessarily correct if PRIORITY frames have been exchanged.

[Scottmitch]

Any thoughts for the preferred way to clarify this? Removing the In this state, no frames have been exchanged. statement will be sufficient but we may then be missing the original meaning this sentence was meant to convey.

[martinthomson]

Closed by #684