scalar: add to 'git help -a' command list

Add 'scalar' as a 'mainporcelain' command in the Git command list. Update
the regex in 'cmd-list.perl' used to match the first line of command
documentation to find 'scalar(1)'.

Helped-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Victoria Dye <vdye@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/Documentation/cmd-list.perl b/Documentation/cmd-list.perl
index af5da45..9515a49 100755
--- a/Documentation/cmd-list.perl
+++ b/Documentation/cmd-list.perl
@@ -10,7 +10,7 @@
 	$state = 0;
 	open I, '<', "$name.txt" or die "No such file $name.txt";
 	while (<I>) {
-		if (/^git[a-z0-9-]*\(([0-9])\)$/) {
+		if (/^(git|scalar)[a-z0-9-]*\(([0-9])\)$/) {
 			$mansection = $1;
 			next;
 		}
diff --git a/command-list.txt b/command-list.txt
index f96bdab..93f94e4 100644
--- a/command-list.txt
+++ b/command-list.txt
@@ -235,3 +235,4 @@
 gittutorial-2                           guide
 gitweb                                  ancillaryinterrogators
 gitworkflows                            guide
+scalar                                  mainporcelain