Stronger Typing for send data?

[MaxClerkwell]

pr #63 merged a function for sending data to a REST-API. I'd strongly encourage to upgrade to stronger typing, a URL might be a validated and constructed object from Skyr URL library, while the message should be validated json object from nlohmann/json.

Would love to get feedback on this.

[R-Abbasi]

The Skyr ULR library looks like a parser to me, and perhaps there should already exist a url at hand for the project, for which the library can be used for parsing.

Creating a nlohmann::json object seems to be simple:

// Creating an object using initializer lists
nlohmann::json j = {
  {"ID", "xzy123"},
  {"VIN", "abcdef321"},
  {"milage", 456},
  {"Comment", "...."},
};