checkout: learn the checkout.guess config variable

If a user does not wish to use DWIM behaviour, they must manually specify git checkout --no-guess each time. Teach checkout and switch to honour the checkout.guess config variable instead.

Changes since v1:

* Replace enumerated priority list with bullet points

Changes since v2:

* Clarify that --guess is the default for checkout in the docs

Denton Liu (2):
Documentation/config/checkout: replace sq with backticks
checkout: learn to respect checkout.guess

 Documentation/config/checkout.txt      | 21 +++++++----
 Documentation/git-checkout.txt         |  5 ++-
 Documentation/git-switch.txt           |  3 ++
 builtin/checkout.c                     |  7 +++-
 contrib/completion/git-completion.bash | 25 ++++++++-----
 t/t2024-checkout-dwim.sh               | 11 ++++++
 t/t2060-switch.sh                      |  5 ++-
 t/t9902-completion.sh                  | 52 ++++++++++++++++++++++++++
 8 files changed, 109 insertions(+), 20 deletions(-)

Range-diff against v2:

1:  f08d3f796a = 1:  f08d3f796a Documentation/config/checkout: replace sq with backticks
2:  2678680a08 ! 2:  eb9daf4bcd checkout: learn to respect checkout.guess

@@ Documentation/config/checkout.txt: will checkout the <something> branch on ano

## Documentation/git-checkout.txt ##
@@ Documentation/git-checkout.txt: branches from there if <branch> is ambiguous but exists on the
+ 'origin' remote. See also checkout.defaultRemote in
linkgit:git-config[1].
+
- Use --no-guess to disable this.
+-Use --no-guess to disable this.
++--guess is the default behavior. Use --no-guess to disable it.
++
+The default behavior can be set via the checkout.guess configuration
+variable.

2.28.0.942.g77c4c6094c