1. renamed lib to to spitlog

2. Rotating bugfix

include/spitlog/sinks/null_sink.h

@@ -0,0 +1,23 @@
+#pragma once
+#include <mutex>
+#include "./base_sink.h"
+#include "../details/null_mutex.h"
+
+
+namespace spitlog {
+namespace sinks {
+
+template <class Mutex>
+class null_sink : public base_sink<Mutex>
+{
+protected:
+    void _sink_it(const details::log_msg&) override
+    {}
+};
+
+typedef null_sink<details::null_mutex> null_sink_st;
+typedef null_sink<std::mutex> null_sink_mt;
+
+}
+}
+