Merge branch 'vd/stash-silence-reset'

"git stash" does not allow subcommands it internally runs as its
implementation detail, except for "git reset", to emit messages;
now "git reset" part has also been squelched.

* vd/stash-silence-reset:
  reset: show --no-refresh in the short-help
  reset: remove 'reset.refresh' config option
  reset: remove 'reset.quiet' config option
  reset: do not make '--quiet' disable index refresh
  stash: make internal resets quiet and refresh index
  reset: suppress '--no-refresh' advice if logging is silenced
  reset: replace '--quiet' with '--no-refresh' in performance advice
  reset: introduce --[no-]refresh option to --mixed
  reset: revise index refresh advice

diff --cc builtin/stash.c
Simple merge

diff --cc t/t3903-stash.sh
Simple merge