Tools like linkgit:git-log[1] or linkgit:git-whatchanged[1], which
normally hide the root commit will now show it. True by default.
+man.viewer::
+ Specify the programs that may be used to display help in the
+ 'man' format. See linkgit:git-help[1].
+
merge.summary::
Whether to include summaries of merged commits in newly created
merge commit messages. False by default.