Bug#748630, 1.4 part of the fix

Bug#748630, Make --help and --version follow GNU standard: 1.4
part.

Rename --daemonize to --background to follow the GNU
convention.

core/tarantool.m

@@ -370,7 +370,7 @@ main(int argc, char **argv)
 #endif
 			   gopt_option('v', 0, gopt_shorts('v'), gopt_longs("verbose"),
 				       NULL, "increase verbosity level in log messages"),
-			   gopt_option('D', 0, gopt_shorts('D'), gopt_longs("daemonize"),
+			   gopt_option('B', 0, gopt_shorts('B'), gopt_longs("background"),
 				       NULL, "redirect input/output streams to a log file and run as daemon"),
 			   gopt_option('h', 0, gopt_shorts('h', '?'), gopt_longs("help"),
 				       NULL, "display this help and exit"),
@@ -512,7 +512,7 @@ main(int argc, char **argv)
 	}
 #endif
 
-	if (gopt(opt, 'D'))
+	if (gopt(opt, 'B'))
 		daemonize(1, 1);
 
 	if (cfg.pid_file != NULL) {

test/box/args.result

@@ -10,7 +10,7 @@ Usage: tarantool_box [OPTIONS]
                           exit
       --init-storage      initialize storage (an empty snapshot file) and exit
   -v, --verbose           increase verbosity level in log messages
-  -D, --daemonize         redirect input/output streams to a log file and run as
+  -B, --background        redirect input/output streams to a log file and run as
                           daemon
   -h, --help              display this help and exit
   -V, --version           print program version and exit
@@ -30,7 +30,7 @@ Usage: tarantool_box [OPTIONS]
                           exit
       --init-storage      initialize storage (an empty snapshot file) and exit
   -v, --verbose           increase verbosity level in log messages
-  -D, --daemonize         redirect input/output streams to a log file and run as
+  -B, --background        redirect input/output streams to a log file and run as
                           daemon
   -h, --help              display this help and exit
   -V, --version           print program version and exit
@@ -59,6 +59,9 @@ tarantool_box --config tarantool.cfg
 tarantool_box: the daemon is already running
 
 tarantool_box --daemonize
+tarantool_box: --daemonize: unknown option
+
+tarantool_box --background
 tarantool_box: the daemon is already running
 
 tarantool_box --version

test/box/args.test

@@ -14,6 +14,7 @@ server.test_option("--config")
 server.test_option("-c")
 server.test_option("--config tarantool.cfg")
 server.test_option("--daemonize")
+server.test_option("--background")
 sys.stdout.pop_filter()
 sys.stdout.push_filter("(\d)\.\d\.\d(-\d+-\w+)?", "\\1.minor.patch-<rev>-<commit>")
 server.test_option("--version")