Config option to limit the number of log files

LogManager.h

@@ -60,7 +60,7 @@ private:
     LogManager(const LogManager&) = delete;
     LogManager(LogManager&&) = delete;
     ~LogManager();
-    std::mutex entry_mutex;
+    std::recursive_mutex entry_mutex;
     std::mutex section_mutex;
     std::ofstream log_stream;
 
@@ -91,6 +91,8 @@ private:
     // A non-guarded flush()
     void _flush();
 
+    void rotate_logs(const filesystem::path& folder, const filesystem::path& templ, int max_count);
+
 public:
     static LogManager* get();
     void configure(json config, const filesystem::path & defaultDir);