Remove deprecated OPTION_BOOLEAN for parsing arguments

As of b04ba2bb4 OPTION_BOOLEAN was deprecated.
This commit removes all occurrences of OPTION_BOOLEAN.
In b04ba2bb4 Junio suggested to replace it with either
OPTION_SET_INT or OPTION_COUNTUP instead. However a pattern, which
occurred often with the OPTION_BOOLEAN was a hidden boolean parameter.
So I defined OPT_HIDDEN_BOOL as an additional possible parse option
in parse-options.h to make life easy.

The OPT_HIDDEN_BOOL was used in checkout, clone, commit, show-ref.
The only exception, where there was need to fiddle with OPTION_SET_INT
was log and notes. However in these two files there is also a pattern,
so we could think of introducing OPT_NONEG_BOOL.

Signed-off-by: Stefan Beller <stefanbeller@googlemail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/builtin/commit.c b/builtin/commit.c
index 003bd7d..b64a083 100644
--- a/builtin/commit.c
+++ b/builtin/commit.c
@@ -1448,12 +1448,10 @@
 		{ OPTION_STRING, 'u', "untracked-files", &untracked_files_arg, N_("mode"), N_("show untracked files, optional modes: all, normal, no. (Default: all)"), PARSE_OPT_OPTARG, NULL, (intptr_t)"all" },
 		/* end commit contents options */
 
-		{ OPTION_BOOLEAN, 0, "allow-empty", &allow_empty, NULL,
-		  N_("ok to record an empty change"),
-		  PARSE_OPT_NOARG | PARSE_OPT_HIDDEN },
-		{ OPTION_BOOLEAN, 0, "allow-empty-message", &allow_empty_message, NULL,
-		  N_("ok to record a change with an empty message"),
-		  PARSE_OPT_NOARG | PARSE_OPT_HIDDEN },
+		OPT_HIDDEN_BOOL(0, "allow-empty", &allow_empty,
+				N_("ok to record an empty change")),
+		OPT_HIDDEN_BOOL(0, "allow-empty-message", &allow_empty_message,
+				N_("ok to record a change with an empty message")),
 
 		OPT_END()
 	};