Touchpanel, document messageFeed

[moinmoin-sh]

Pullrequest with information https://github.com/OXRS-IO/OXRS-IO-TouchPanel-ESP32-FW/pull/38

sample payload

{
"tiles":
  [
    {
    "screen":"1",
    "tile":"2",
    "messageFeed":
       {
       "addPost":
          {
        "id":1,
        "head":"#ff0000 Taffic Announcement#", 
        "body":"Route 66 closed for motorcycles\nUse public transportation"
      }
       }
    },
    {
    "screen":"1",
    "tile":"2",
    "messageFeed":
       {
       "addPost":
          {
        "id":2,
        "head":"This is a #0000ff Heading# which can span multiple lines", 
        "body":"Feed content goes here\nAnd a second line \n#00ff00 Third# line"
      }
       }
    }
  ]
}