[PATCH 0/9] emacs: Unify common key bindings and lots more

[Austin Clements]

This series moves several common key bindings into a shared
notmuch-wide keymap.  To get there, it first cleans up several things
so that all notmuch modes have common commands to put into a common
keymap.

In the process, this fixes inconsistent sort ordering reported in
id:m2bo5c5h8l.fsf at ramakrmu-mac.i-did-not-set--mail-host-address--so-tickle-me,
improves the currently fragile hello refresh behavior, combines
several mostly-duplicated commands, and improves the notmuch-help
implementation.

This passes all of the tests and basic interactive testing, but it
would be good for people to exercise it.