+.
Show last client activity time in default choose-client list.
Add .mailmap for commit author translations

Because it's not possible to enumerate up-front all of the committers to
tmux coming from OpenBSD, at the time a commit is imported in to git from
the OpenBSD CVS repository, the author information is not known to Git,
necessarily.

But it's possible to alter for output the respective author after the fact,
via Git's .mailmap file.  It is this file which will therefore provide a new
mapping of OpenBSD commiter to an actual real name and real email address.
Merge branch 'obsd-master'

Sync from OpenBSD.
Sanitise additional .mailmap entries

This sanitises multiple author addresses some more, mapping them back to one
common entity.
Use a utility function for common code to show errors in config file,
from Thomas Adam.
Clarify some points about config files, notably that they are only read
at server start. From Thomas Adam.
Add halfpage commands to mode command string table (missed by accident),
from Thomas Adam.
Merge branch 'obsd-master'

Sync from OpenBSD.

* obsd-master:
  Add halfpage commands to mode command string table (missed by accident), from Thomas Adam.
  Clarify some points about config files, notably that they are only read at server start. From Thomas Adam.
  Use a utility function for common code to show errors in config file, from Thomas Adam.
Put helper function back, will be needed in a bit.
Merge branch 'master' of ssh://tmux.git.sourceforge.net/gitroot/tmux/tmux
Merge branch 'obsd-master'

Sync from OpenBSD.
Call realpath earlier on the socket directory path rather than on the
socket file path because the latter may not exist yet and in that case
realpath is allowed to fail. From Romain Francoise.
Fix session choice so that preferring unattached sessions actually
works, reported by Drew Frank.
Add window-status-last-* options, from Boris Faure.
Revert last, after discussion it isn't necessary.
When scrolling in copy mode with the mouse, scroll screen rather than
moving cursor. This change from Ailin Nemui, alternative to a change
from Stephen Hicks.
Allow cmd-run-shell to accept -t to specify the pane to display the
output, requested by Alexander Tsepkov.
Correctly aggregate together errors from nested config files (with
source-file). Fix by Thomas Adam, reported by Sam Livingstone-Gray
Merge branch 'obsd-master'

Sync from OpenBSD.