status: add optional stash count information

Introduce '--show-stash' and its configuration option 'status.showStash'
to allow git-status to show information about currently stashed entries.

Signed-off-by: Liam Beguin <liambeguin@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/builtin/commit.c b/builtin/commit.c
index ef52457..c089fb8 100644
--- a/builtin/commit.c
+++ b/builtin/commit.c
@@ -1295,6 +1295,10 @@ static int git_status_config(const char *k, const char *v, void *cb)
 		status_deferred_config.show_branch = git_config_bool(k, v);
 		return 0;
 	}
+	if (!strcmp(k, "status.showstash")) {
+		s->show_stash = git_config_bool(k, v);
+		return 0;
+	}
 	if (!strcmp(k, "status.color") || !strcmp(k, "color.status")) {
 		s->use_color = git_config_colorbool(k, v);
 		return 0;
@@ -1343,6 +1347,8 @@ int cmd_status(int argc, const char **argv, const char *prefix)
 			    N_("show status concisely"), STATUS_FORMAT_SHORT),
 		OPT_BOOL('b', "branch", &s.show_branch,
 			 N_("show branch information")),
+		OPT_BOOL(0, "show-stash", &s.show_stash,
+			 N_("show stash information")),
 		{ OPTION_CALLBACK, 0, "porcelain", &status_format,
 		  N_("version"), N_("machine-readable output"),
 		  PARSE_OPT_OPTARG, opt_parse_porcelain },