Support for IPv6 DNS records (AAAA) and IPv6 Ping for ESP32 and ESP8266

[s-hadinger]

Description:

Numerous improvements to IPv6 support:

• DNS resolution now works with AAAA IPv6 records
• SetOption149 allows to prioritize AAAA (v6) records over A (v4) records, disabled by default. However if no IPv6 global address is assigned to the device, the resolution is done with v4 addresses
• Patch to solve a bug that would reset DNS servers when Ethernet is connected but Wifi is trying to connect
• Removal of DnsClient library in favor of LWIP, patched to support time-out
• Support for Ping with IPv6 targets (ICMP6)

Related issue (if applicable): fixes #

Checklist:

• The pull request is done against the latest development branch
• Only relevant files were touched
• Only one feature/fix was added per PR and the code change compiles without warnings
• The code change is tested and works with Tasmota core ESP8266 V.2.7.4.9
• The code change is tested and works with Tasmota core ESP32 V.2.0.5
• I accept the CLA.

NOTE: The code change must pass CI tests. Your PR cannot be merged unless tests pass