Add new HTTPS and SVCB record types

[bluejekyll]

@briansmith @djc @sayrer @moonshiner

Ok, had some time today, through these record types in.

Some notes, currently this does not validate the SvcbParamValue against the SvcbParamKey type.
Currently this is not supported in the Zone file for the server, but that shouldn't be too hard, so I think I'll leave this in draft until I can do that.

This can be tested with:

$> cargo install --git https://github.com/bluejekyll/trust-dns.git --branch https_and_svcb --bin resolve -- trust-dns-util
$> resolve -t HTTPS crypto.cloudflare.com
crypto.cloudflare.com. 273 IN HTTPS 1 . alpn=h2, ipv4hint=162.159.135.79,162.159.136.79, echconfig="/gkAQwATY2xvdWRmbGFyZS1lc25pLmNvbQAgSiSc2sO3T91QP7ZBkmxa4DBEHReUB0M5UXn3iFQpvW8AIAAEAAEAAQAAAAA=" ipv6hint=2606:4700:7::a29f:874f,2606:4700:7::a29f:884f,

see: https://github.com/MikeBishop/dns-alt-svc

fixes: #1323

[codecov]

Codecov Report

Merging #1402 (d14af60) into main (5f68b7d) will decrease coverage by 1.43%.
The diff coverage is 67.09%.

@@            Coverage Diff             @@
##             main    #1402      +/-   ##
==========================================
- Coverage   85.10%   83.67%   -1.43%     
==========================================
  Files         153      167      +14     
  Lines       15042    15872     +830     
==========================================
+ Hits        12801    13280     +479     
- Misses       2241     2592     +351     

[djc]

LGTM so far.

[bluejekyll]

Ok, I fixed all the SvcParamValue encoders and decoders. I think everything is fully functional now. For completeness, I want to add the Zone file parsers too before this is ready to merge.

[bluejekyll]

Ok, @djc, I think this is ready to merge... we have full end-to-end support now for server, client, and resolver now.

[djc]

There's just too much code here for me to closely review. I presume most of it is based on copy/pasting from other places? It's probably fine, we'll iron out any bugs as it starts getting used I suppose.

[bluejekyll]

Sorry, for the amount of code... I tried to do it in stages to build up the entire thing... but yeah, in the end I don't see a way to make this smaller than handling all of these cases.

[bluejekyll]

If it helps, I think it's all perfect ;)

[bluejekyll]

just rebased.