Rename sections from "module" to "submodule" in .gitmodules

Rename [module] to [submodule], so that it would be more
forward compatible with the proposed extension by harmonizing
the section names used in .gitmodules and .git/config.
Signed-off-by: NLars Hjemli <hjemli@gmail.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

git-submodule.sh

@@ -66,7 +66,7 @@ modules_init()
 		url=$(git-config submodule."$path".url)
 		test -z "$url" || continue
 
-		url=$(GIT_CONFIG=.gitmodules git-config module."$path".url)
+		url=$(GIT_CONFIG=.gitmodules git-config submodule."$path".url)
 		test -z "$url" &&
 		die "No url found for submodule '$path' in .gitmodules"
 

t/t7400-submodule-basic.sh

@@ -40,7 +40,7 @@ test_expect_success 'Prepare submodule testing' '
 	git-add a lib z &&
 	git-commit -m "super commit 1" &&
 	mv lib .subrepo &&
-	GIT_CONFIG=.gitmodules git-config module.lib.url git://example.com/lib.git
+	GIT_CONFIG=.gitmodules git-config submodule.lib.url git://example.com/lib.git
 '
 
 test_expect_success 'status should only print one line' '