Merge branch 'hn/checkout-track-fetch' into seen

"git checkout --track=..." learned to optionally fetch the branch
from the remote the new branch will work with.

* hn/checkout-track-fetch:
  checkout: extend --track with a "fetch" mode to refresh start-point
  branch: expose helpers for finding the remote owning a tracking ref

diff --cc Documentation/git-checkout.adoc
Simple merge

diff --cc Documentation/git-switch.adoc
Simple merge

diff --cc builtin/checkout.c
index b78b3a1d16def48852204be587c9131d5fb5363d,358783af170e6047c87f0b9df461d7398a7d62c8..37caceaefd7190aa4b43f12a37062926bab4c7b6
--- 1/builtin/checkout.c
--- 2/builtin/checkout.c
+++ b/builtin/checkout.c
@@@ -29,10 -31,8 +30,11 @@@
  #include "repo-settings.h"
  #include "resolve-undo.h"
  #include "revision.h"
+ #include "run-command.h"
 +#include "sequencer.h"
  #include "setup.h"
 +#include "sparse-index.h"
 +#include "strvec.h"
  #include "submodule.h"
  #include "symlinks.h"
  #include "trace2.h"

diff --cc t/t7201-co.sh
Simple merge