remote: add promisor and partial clone config to the doc

diff --git a/Documentation/git-difftool.txt b/Documentation/git-difftool.txt
index 96c26e6aa82c98da1652023f0d04b4b63c8a4944..484c485fd06c9d52e09b5e7324f5f13fd444e4f9 100644 (file)
--- a/Documentation/git-difftool.txt
+++ b/Documentation/git-difftool.txt
@@ -90,7 +90,9 @@ instead.  `--no-symlinks` is the default on Windows.
        When 'git-difftool' is invoked with the `-g` or `--gui` option
        the default diff tool will be read from the configured
        `diff.guitool` variable instead of `diff.tool`. The `--no-gui`
-       option can be used to override this setting.
+       option can be used to override this setting. If `diff.guitool`
+       is not set, we will fallback in the order of `merge.guitool`,
+       `diff.tool`, `merge.tool` until a tool is found.
 
 --[no-]trust-exit-code::
        'git-difftool' invokes a diff tool individually on each file.