Create a long string text field

I was trying to read a text file into a sensor with

- platform: command_line
  name: custom_ls
  command: "ls"
  scan_interval: 60

This would not create the sensor because the return value was > 255 characters. Allowing sensors and input_textbox fields to have strings larger than 255 characters would permit one to populate a markdown field in lovelace. If a long string field existed, and you could overload objects that used a regular “short” string with this type would allow people to design a richer UI experience.