command-list: prepare machinery for upcoming "common groups" section

The ultimate goal is for "git help" to classify common commands by
group. Toward this end, a subsequent patch will add a new "common
groups" section to command-list.txt preceding the actual command list.
As preparation, teach existing command-list.txt parsing machinery, which
doesn't care about grouping, to skip over this upcoming "common groups"
section.

Signed-off-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Sébastien Guimmara <sebastien.guimmara@gmail.com>
Reviewed-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Documentation/cmd-list.perl

@@ -38,6 +38,10 @@ sub format_one {
 	}
 }
 
+while (<>) {
+	last if /^### command list/;
+}
+
 my %cmds = ();
 for (sort <>) {
 	next if /^#/;

Makefile

@@ -2447,15 +2447,16 @@ check-docs::
 		esac ; \
 		test -f "Documentation/$$v.txt" || \
 		echo "no doc: $$v"; \
-		sed -e '/^#/d' command-list.txt | \
+		sed -e '1,/^### command list/d' -e '/^#/d' command-list.txt | \
 		grep -q "^$$v[ 	]" || \
 		case "$$v" in \
 		git) ;; \
 		*) echo "no link: $$v";; \
 		esac ; \
 	done; \
 	( \
-		sed -e '/^#/d' \
+		sed -e '1,/^### command list/d' \
+		    -e '/^#/d' \
 		    -e 's/[ 	].*//' \
 		    -e 's/^/listed /' command-list.txt; \
 		$(MAKE) -C Documentation print-man1 | \

command-list.txt

@@ -1,4 +1,4 @@
-# List of known git commands.
+### command list (do not change this line)
 # command name                          category [deprecated] [common]
 git-add                                 mainporcelain common
 git-am                                  mainporcelain