[Feature] DapperJson attribute

[tracker1]

Given that JSON strings are first class citizens in many modern databases, it would be nice, if there was an easy way to decorate a property using an attribute that would trigger JSON serialization/deserialization to/from database calls.

Note: this should handle enumerables as a JSON array, where objects will be the object structure. This should probably use the default json serialization for .Net Core/5+ with a minimal/default configuration, that can possibly be extended or overridden.

class Foo {
  [DapperJson]
  IEnumerable<Bar> somePropertyList { get; set; }

  [DapperJson]
  Bar someProperty { get; set; }
}

Related to #688