Dispatcher example in README does not compile

[OLEGSHA]

From README.md:

struct Order
{
    // (comment)
    std::string ticker;

    handler("ticker", [](Order& o, value v) {v.to(o.ticker);}),

Attempting to compile this code causes value::as<std::string> to fail because std::string_view must be used instead. Indeed, Order::ticker is an std::string_view in test/dispatcher.cpp.