Add OLED health function

src/main.cpp

@@ -37,6 +37,14 @@ void statusMsg(String msg){
   }while ( disp.nextPage() );
 }
 
+void screenRefresh(){
+  // Fill screen
+  disp.setDrawColor(0);
+  disp.drawBox(0, 0, 128, 64);
+  delay(20);
+  disp.setDrawColor(1);
+}
+
 void configModeCallback (WiFiManager *myWiFiManager) {
   Serial.println("Entered config mode");
   statusMsg("Setup");
@@ -151,6 +159,10 @@ void loop(void) {
     disp.setDrawColor(1);
     drawUI();
     drawProgress();
+    if(millis() % 500 <= 2){
+      Serial.println("Refreshing");
+      screenRefresh();
+    }
   }while ( disp.nextPage() );
 
   // TODO: Replace this with data fetch