merge.tool::
Controls which merge resolution program is used by
gitlink:git-mergetool[l]. Valid values are: "kdiff3", "tkdiff",
- "meld", "xxdiff", "emerge", "vimdiff"
+ "meld", "xxdiff", "emerge", "vimdiff", and "opendiff"
merge.verbosity::
Controls the amount of output shown by the recursive merge