utility: added log levels for Loggers

This change allows setting log levels on loggers. The apps ConsoleLogger was switched to only logging warnings and
errors the FileLogger still saves all types of logs.

src/lib/utility/logging/FileLogger.h

@@ -12,11 +12,11 @@ public:
 	FileLogger();
 	virtual ~FileLogger();
 
+private:
 	virtual void logInfo(const LogMessage& message);
 	virtual void logWarning(const LogMessage& message);
 	virtual void logError(const LogMessage& message);
 
-private:
 	static const std::string s_filePath;
 
 	void setupFileName();