Add AsyncESP8266_Ethernet_Manager library

[khoih-prog]

Releases v1.0.0

1. Initial coding to port ESPAsync_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/AsyncESP8266_Ethernet_Manager:

Linting library in AsyncESP8266_Ethernet_Manager
WARNING: library.properties name value AsyncESP8266_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

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Linting sketch in AsyncESP8266_Ethernet_Manager/examples/Async_ConfigOnDoubleReset

Linter results for project: no errors or warnings

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Linting sketch in AsyncESP8266_Ethernet_Manager/examples/Async_ConfigOnDoubleReset_TZ

Linter results for project: no errors or warnings

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Linting sketch in AsyncESP8266_Ethernet_Manager/examples/Async_ConfigOnSwitch

Linter results for project: no errors or warnings

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Linting sketch in AsyncESP8266_Ethernet_Manager/examples/Async_ConfigOnSwitchFS

Linter results for project: no errors or warnings

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Linting sketch in AsyncESP8266_Ethernet_Manager/examples/Async_ConfigPortalParamsOnSwitch

Linter results for project: no errors or warnings

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Linting sketch in AsyncESP8266_Ethernet_Manager/examples/Async_ESP_FSWebServer

Linter results for project: no errors or warnings

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Linting sketch in AsyncESP8266_Ethernet_Manager/examples/Async_ESP_FSWebServer_DRD

Linter results for project: no errors or warnings

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Linter results for projects: 0 ERRORS, 1 WARNINGS

[github-actions]

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