Add ESP8266_Ethernet_Manager library

[khoih-prog]

Releases v1.0.0

1. Initial coding to port synchronous ESP_WiFiManager to ESP8266 boards using LwIP W5500 / W5100(S) / ENC28J60 Ethernet.
2. Use allman astyle

[github-actions]

Arduino Lint has suggestions for possible improvements to https://github.com/khoih-prog/ESP8266_Ethernet_Manager:

Linting library in ESP8266_Ethernet_Manager
WARNING: library.properties name value ESP8266_Ethernet_Manager is longer than the recommended length of 16 characters.
         See: https://arduino.github.io/arduino-cli/latest/library-specification/#libraryproperties-file-format        
         (Rule LP010)                                                                                                  

Linter results for project: 0 ERRORS, 1 WARNINGS

-------------------

Linting sketch in ESP8266_Ethernet_Manager/examples/ConfigOnDoubleReset

Linter results for project: no errors or warnings

-------------------

Linting sketch in ESP8266_Ethernet_Manager/examples/ConfigOnDoubleReset_TZ

Linter results for project: no errors or warnings

-------------------

Linting sketch in ESP8266_Ethernet_Manager/examples/ConfigOnSwitch

Linter results for project: no errors or warnings

-------------------

Linting sketch in ESP8266_Ethernet_Manager/examples/ConfigOnSwitchFS

Linter results for project: no errors or warnings

-------------------

Linting sketch in ESP8266_Ethernet_Manager/examples/ConfigPortalParamsOnSwitch

Linter results for project: no errors or warnings

-------------------

Linting sketch in ESP8266_Ethernet_Manager/examples/ESP_FSWebServer

Linter results for project: no errors or warnings

-------------------

Linting sketch in ESP8266_Ethernet_Manager/examples/ESP_FSWebServer_DRD

Linter results for project: no errors or warnings

-------------------

Linter results for projects: 0 ERRORS, 1 WARNINGS

[github-actions]

Your submission has now been accepted! Thanks for your contribution to the Arduino Library Manager index.

The library(s) will be available for installation via Library Manager within a day's time.

You can check the logs from the Library Manager indexer for your library(s) here:
http://downloads.arduino.cc/libraries/logs/github.com/khoih-prog/ESP8266_Ethernet_Manager/