Whether to include summaries of merged commits in newly created
merge commit messages. False by default.
+merge.tool::
+ Controls which merge resolution program is used by
+ gitlink:git-mergetool[l]. Valid values are: "kdiff3", "tkdiff",
+ "meld", "xxdiff", "emerge"
+
merge.verbosity::
Controls the amount of output shown by the recursive merge
strategy. Level 0 outputs nothing except a final error