Major Releases v1.7.0 to use auto-TZ

### Major Releases v1.7.0

1. Add auto-Timezone feature with variable `_timezoneName` (e.g. `America/New_York`) and function to retrieve TZ (e.g. `EST5EDT,M3.2.0,M11.1.0`) to use directly to configure ESP32/ESP8266 timezone. Check [How to retrieve timezone? #51](khoih-prog/ESPAsync_WiFiManager#51) for more info.
2. Store those `_timezoneName` and `TZ` in LittleFS or SPIFFS config file.
3. Using these new timezone feature is optional.
4. Add checksum in config file to validate data read from LittleFS or SPIFFS config file.
5. Update examples to show how to use the new TZ feature.

Author: khoih-prog

README.md

@@ -167,9 +167,11 @@
   * [7. ConfigOnDoubleReset on ESP32_DEV](#7-configondoublereset-on-esp32_dev)
     * [7.1 DRD => Config Portal](#71-drd--config-portal)
     * [7.2 Data Saved => Connect to WiFi with correct local time, TZ set and using NTP](#72-data-saved--connect-to-wifi-with-correct-local-time-tz-set-and-using-ntp)
-  * [8. ConfigOnDoubleReset on ESP32_DEV](#8-configondoublereset-on-esp32_dev)
+    * [7.3 Normal running with correct local time, TZ set and using NTP](#73-normal-running-with-correct-local-time-tz-set-and-using-ntp)
+  * [8. ConfigOnDoubleReset on ESP32S2_DEV](#8-configondoublereset-on-esp32s2_dev)
     * [8.1 No Data => Config Portal](#81-no-data--config-portal)
     * [8.2 Data Saved => Connect to WiFi with correct local time, TZ set and using NTP](#82-data-saved--connect-to-wifi-with-correct-local-time-tz-set-and-using-ntp)
+    * [8.3 Normal running with correct local time, TZ set and using NTP](#83-normal-running-with-correct-local-time-tz-set-and-using-ntp)
 * [Debug](#debug)
 * [Troubleshooting](#troubleshooting)
 * [Issues](#issues)