HASPmota support for spangroup (styled text)

[s-hadinger]

Description:

Fixed LVGL support for spangroup, and extended HASPmota to support spangroup.

Spangroup is equivalent to HTML <span> and allows to have a text area composed of multiple fragments, each fragment with its own style, size, font, color...

The spangroup above was obtained with:

{"id":11,"obj":"spangroup","x":0,"y":60,"w":300,"h":115,"text_font":"montserrat-20","bg_color":"#000088","bg_opa":255}
  {"id":12,"obj":"span","parentid":11,"text":"This is "}
  {"id":13,"obj":"span","parentid":11,"text":"RED","text_color":"#FF0000","text_font":"montserrat-28"}
  {"id":12,"obj":"span","parentid":11,"text":"and this is "}
  {"id":14,"obj":"span","parentid":11,"text":"GREEN","text_color":"#00FF00","text_font":"montserrat-28","text_decor":1}
  {"id":15,"obj":"span","parentid":11,"text":" underlined"}
  {"id":16,"obj":"span","parentid":11,"text":"\nAnd this is almost transparent","text_opa":100}

You must first define a spangroup object, and add as many as span sub-objects. You need to define the parentid attribute to the spangroup.

Note: span are parsed in the order in the jsonl file, not by id number.

Text from span can be updated via rules, like normal HASPmota text.

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.2.0.14
• I accept the CLA.

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