sfbis: ABNF appendix

[reschke]

"This section uses the Augmented Backus-Naur Form (ABNF) notation [RFC5234] to illustrate expected syntax of Structured Fields. In doing so, it uses the VCHAR, SP, DIGIT, ALPHA, and DQUOTE rules from [RFC5234]. It also includes the tchar and OWS rules from [RFC7230]."

Minor issues:

• should refer to RFC9110
• VCHAR is actually not used in the ABNF but in prose earlier in the spec; it probably would be better to move this paragraph back to "1.2. Notational Conventions".

[reschke]

I don't think that's sufficient (see for instance the preceding sentence mentioning DQUOTE).

[mnot]

How's that?

[reschke]

LGTM, thanks.