- implement generic support for on-device battery powered RTC Modules.

- implement support for I2C RV-3028 based RTC modules like the RAK12002
- pretty print some debug timestamps

src/main.cpp

@@ -79,6 +79,9 @@ uint8_t cardkb_found;
 // The I2C address of the Faces Keyboard (if found)
 uint8_t faceskb_found;
 
+// The I2C address of the RTC Module (if found)
+uint8_t rtc_found;
+
 bool eink_found = true;
 
 uint32_t serialSinceMsec;