Add command WebRun (as WebQuery extension)

[barbudor]

Description:

Related issue (if applicable): fixes #21325

This command is not included by default and requires a self-compile with

#defined USE_WEBRUN

It uses 0.5k of code

Syntax:

WebRun http://someserver/somepath/somecommandfile

Execute the Tasmota commands from the downloaded text file.
Format is similar to the .bat file that can be executed by UfsRun from the file system:

• 1 command per line
• accept backlog command
• leading spaces are ignored
• line starting by ; is considered as a comment and is ignored
• empty line is ignored

It is implemented as an extension of WebQuery so it also supports all additional arguments of WebQuery

• method (default to GET when not specified, must be specified if other arguments are used)
  Side effect: GET is now default method for WebQuery too when not specified.
• headers (between [ ]) => for example for authentication
• body

Note: WebSend is not modified, just moved below WebQuery

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.2.7.6
• The code change is tested and works with Tasmota core ESP32 V.3.0.0
• I accept the CLA.

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

[barbudor]

@arendst, no plan to merge ?