remove some dead code

fix #1225

mitigate a potential DoS against websocket listeners

Update draft/rename impl

Link to the new draft PR:
<https://github.com/ircv3/ircv3-specifications/pull/420>

Changes in the spec:

- Use standard replies instead of numerics:
  <https://github.com/ircv3/ircv3-specifications/pull/420/files#diff-70e90beef48dc9cf5d784d1e179ea822R44>
- Allow RENAME to a different case:
  <https://github.com/ircv3/ircv3-specifications/pull/420/files#diff-70e90beef48dc9cf5d784d1e179ea822R42>

This commit makes oragono send the PART-JOIN fallback even on case-only
changes. This is so that clients don't have to worry about oragono's
UTF8 casefolding. See the following comments for further info:
<https://github.com/ircv3/ircv3-specifications/pull/420#issuecomment-668770837>

Misc fixes:

- Remove unused variable,
- Add missing calls to utils.SafeErrorParam,
- Don't fill replies with the user-provided "oldName", for the same
  reason as sending the PART-JOIN fallback.

Websocket listeners would process an arbitrary number of invalid
(non-text or blank) messages without throttling. This imposes fakelag
on such messages by treating them as blank lines.

minor refactoring

make it easier to patch out the maximum line length

Since allocating them is rare.

New Crowdin updates

fix an edge case with `/NS SASET user always-on true`

If force-nick-equals-account is disabled, then this could cause
a client with a non-reserved (or grouped) nick to become always-on.
(This can't happen with `/NS SET always-on true` because we check in
advance.)

clean up always-on state machine

fix #1204

fix #1190

bump to new development version, upgrade dependencies

documentation updates for release

fix #1214

New Crowdin updates