travis-ci: switch to Xcode 10.1 macOS image

diff --git a/Documentation/git-mergetool.txt b/Documentation/git-mergetool.txt
index e846c2ed7f7f862f5324c0e95a2b17dabcaac58d..0c7975a0507a35f9624516f0844ad11cd5141d50 100644 (file)
--- a/Documentation/git-mergetool.txt
+++ b/Documentation/git-mergetool.txt
@@ -79,6 +79,24 @@ success of the resolution after the custom tool has exited.
        Prompt before each invocation of the merge resolution program
        to give the user a chance to skip the path.
 
+-g::
+--gui::
+       When 'git-mergetool' is invoked with the `-g` or `--gui` option
+       the default merge tool will be read from the configured
+       `merge.guitool` variable instead of `merge.tool`.
+
+--no-gui::
+       This overrides a previous `-g` or `--gui` setting and reads the
+       default merge tool will be read from the configured `merge.tool`
+       variable.
+
+-O<orderfile>::
+       Process files in the order specified in the
+       <orderfile>, which has one shell glob pattern per line.
+       This overrides the `diff.orderFile` configuration variable
+       (see linkgit:git-config[1]).  To cancel `diff.orderFile`,
+       use `-O/dev/null`.
+
 TEMPORARY FILES
 ---------------
 `git mergetool` creates `*.orig` backup files while resolving merges.