use true and false for boolean properties

So that it's easier to convert them to booleans in introspection
code later.

src/daemon/main.c

@@ -92,7 +92,7 @@ int main(int argc, char *argv[])
 	properties = pw_properties_new(
                                 PW_KEY_CORE_NAME, daemon_name,
                                 PW_KEY_CONTEXT_PROFILE_MODULES, "none",
-                                PW_KEY_CORE_DAEMON, "1", NULL);
+                                PW_KEY_CORE_DAEMON, "true", NULL);
 
 	/* parse configuration */
 	config = pw_daemon_config_new(properties);