cmdline: Print available protocols when --version is run.

src/cmdline.c

@@ -23,6 +23,7 @@
 #include "decoder_list.h"
 #include "config.h"
 #include "audioOutput.h"
+#include "ls.h"
 
 #ifdef ENABLE_ARCHIVE
 #include "archive_list.h"
@@ -63,6 +64,10 @@ static void version(void)
 	archive_plugin_print_all_suffixes(stdout);
 #endif
 
+	puts("\n"
+	      "Supported protocols:\n");
+	print_supported_uri_schemes_to_fp(stdout);
+
 	exit(EXIT_SUCCESS);
 }