Merge remote-tracking branch 'origin/master' into repobrowse

* origin/master: (25 commits)
  evcleanup: ensure deferred close from timers are handled ASAP
  httpd/async: improve variable naming
  githttpbackend: minor cleanups to improve readability
  githttpbackend: simplify compatibility code
  githttpbackend: minor readability improvement
  http: fix clobbering of $null_io
  linkify: modify argument in place
  view: do not modify array during iteration
  view: stop chomping off whitespace at ends of messages
  view: remove unused parameter
  search: lookup_mail handles modified DBs
  doc: various comments on async handling
  searchthread: simplify API and remove needless OO
  searchthread: update comment about loop prevention
  searchmsg: remove ensure_metadata
  tests: add thread-all testing for benchmarking
  searchmsg: do not memoize {date} field
  searchmsg: remove locale-dependency for ->date
  t/config.t: fix feedmax default
  wwwtext: link to RFC4685 (Atom Threading)
  ...

diff --cc MANIFEST
Simple merge

diff --cc lib/PublicInbox/GitHTTPBackend.pm
Simple merge