Allow the rerere mechanism to update the index with the
result of auto-conflict resolution if possible.
+--overwrite-ignore::
+--no-overwrite-ignore::
+ Silently overwrite ignored files from the merge result. This
+ is the default behavior. Use `--no-overwrite-ignore` to abort.
+
--abort::
Abort the current conflict resolution process, and
try to reconstruct the pre-merge state.