fix two WHO bugs

These should have been committed in 8218d1caab
but weren't.

fix #1833

fix casefolding issue in muting RELAYMSG

update dependencies for 2.9 window

Reported by @mogad0n; the mute mask was being case-canonicalized,
but the RELAYMSG identifier wasn't being case-canonicalized before
the check.

`WHO #channel o` is supposed to return only server operators.
This is RFC1459 cruft; just return an empty list in this case.

RPL_ENDOFWHO should send the original, un-normalized mask

Modernize the list of os-arch pairs that get official release builds;
add darwin/arm64 and openbsd/amd64, remove 386 and armv7, add plan9/amd64
for fun.

The landing page link doesn't seem to work right now.

bump changelog for 2.8.0, fix #1827

Improve documentation for use of certificate fingerprints

Document operator capabilities.

SAMODE +f shouldn't require channel privileges

Reported by @Mikaela; normally this requires +o or higher on the
channel that is the target of the forward, but SAMODE should bypass
this check.

fix error message for NS SET EMAIL without the password

temporary logo update

Languages README.md: Oragono -> Ergo

Signed-off-by: Georg <georg@lysergic.dev>

Thanks @brettgilio!

bump changelog and version for 2.8.0-rc1

fix some inconsistencies in how git hashes and tags are included in the binary

docker: downgrade alpine to 3.13 again

See https://wiki.alpinelinux.org/wiki/Release_Notes_for_Alpine_3.14.0#faccessat2 ;
this maintains compatibility with older, buggy versions of docker and runc.
Alpine 3.13 is supported until 2022-11-01.

CHATHISTORY with nonexistent msgid should send empty batch

fix case where CS TRANSFER as an operator required acceptance

It was sending MESSAGE_ERROR, which was inappropriate. Send an empty batch
for now (this is at parity with the in-memory implementation).

Reported by @mogad0n. If a user had both operator privileges and
channel owner privileges, the CS TRANSFER would proceed as though
unprivileged, requiring acceptance by the receiving user. Fix this
to not require acceptance.

docker: Error response from daemon: failed to create shim: OCI runtime create failed: container_linux.go:380: starting container process caused: exec: "/ircd-bin/run.sh": permission denied: unknown.

See #1808

fix #1676, take 2

fix #1802