Version number, name, and build details.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

version.h

@@ -0,0 +1,11 @@
+#ifndef LIGHTNING_VERSION_H
+#define LIGHTNING_VERSION_H
+#include <ccan/opt/opt.h>
+
+char *version_and_exit(const void *unused);
+
+#define opt_register_version()						\
+	opt_register_noarg("--version|-V", version_and_exit, NULL,	\
+			   "print version to standard output and exit")
+
+#endif /* LIGHTNING_VERSION_H */