v1.6.4 for ESP32 + LwIP W6100

#### Releases v1.6.4

1. Initial coding to port [ESPAsyncWebServer](https://github.com/me-no-dev/ESPAsyncWebServer) to ESP32 boards using `LwIP W6100 Ethernet`.
2. Bump up to `v1.6.4` to sync with [AsyncWebServer_ESP32_W5500 v1.6.4](https://github.com/khoih-prog/AsyncWebServer_ESP32_W5500)
3. Use `allman astyle`

Author: khoih-prog

README.md

@@ -16,7 +16,7 @@
 ## Table of contents
 
 * [Table of contents](#table-of-contents)
-* [Important Note from v1.6.2](#Important-Note-from-v162)
+* [Important Note](#Important-Note)
 * [Why do we need this AsyncWebServer_ESP32_W6100 library](#why-do-we-need-this-AsyncWebServer_ESP32_W6100-library)
   * [Features](#features)
   * [Why Async is better](#why-async-is-better)