add logging class (not working version)

src/items/LoggingClass.cpp

@@ -0,0 +1,25 @@
+#include "items/LoggingClass.h"
+
+LoggingClass::LoggingClass(unsigned long period, unsigned int maxPoints, String key) {
+    _period = period;
+    _maxPoints = maxPoints;
+    _key = key;
+}
+
+LoggingClass::~LoggingClass() {}
+
+void LoggingClass::loop() {
+    currentMillis = millis();
+    difference = currentMillis - prevMillis;
+    if (difference >= _period) {
+        prevMillis = millis();
+        writeDate();
+    }
+}
+
+void LoggingClass::writeDate() {
+    SerialPrint("I", "Logging", _key);
+}
+
+std::vector<LoggingClass*> myLogging;
+//LoggingClass* myLogging;