Don't resend *all* packets in version negotiation

[ekr]

"
When the client receives a Version Negotiation packet from the
server, it should select an acceptable protocol version. If the
server lists an acceptable version, the client selects that version
and resends all packets using that version. The resent packets MUST
use new packet numbers. These packets MUST continue to have the
VERSION flag set and MUST include the new negotiated protocol
version."

There might be some packets which should not be re-sent if, for instance, they are not relevant for this version of QUIC

[ianswett]

Also, given they have new packet numbers and the framing of a version may change, we should talk about retransmitting frames, not packets in this section.

[martinthomson]

I think that this instead needs to say something more generic: start over. Marking this as editorial (let me know if you disagree).

[ianswett]

Agreed, start over is the correct answer.

[martinthomson]

The new text is better:

If the server lists an acceptable version, the client selects that version and reattempts to create a connection using that version.