merge(3p/git): Merge git subtree at v2.29.2 r/1890

This also bumps the stable nixpkgs to 20.09 as of 2020-11-21, because
there is some breakage in the git build related to the netrc
credentials helper which someone has taken care of in nixpkgs.

The stable channel is not used for anything other than git, so this
should be fine.

Change-Id: I3575a19dab09e1e9556cf8231d717de9890484fb

1 files changed, 10 insertions, 0 deletions

diff --git a/third_party/git/Documentation/config/merge.txt b/third_party/git/Documentation/config/merge.txt
index 6a313937f8c0..cb2ed589075b 100644
--- a/third_party/git/Documentation/config/merge.txt
+++ b/third_party/git/Documentation/config/merge.txt
@@ -70,6 +70,16 @@ merge.stat::
 	Whether to print the diffstat between ORIG_HEAD and the merge result
 	at the end of the merge.  True by default.
 
+merge.autoStash::
+	When set to true, automatically create a temporary stash entry
+	before the operation begins, and apply it after the operation
+	ends.  This means that you can run merge on a dirty worktree.
+	However, use with care: the final stash application after a
+	successful merge might result in non-trivial conflicts.
+	This option can be overridden by the `--no-autostash` and
+	`--autostash` options of linkgit:git-merge[1].
+	Defaults to false.
+
 merge.tool::
 	Controls which merge tool is used by linkgit:git-mergetool[1].
 	The list below shows the valid built-in values.