Remove non-std lib example.

README.md

@@ -430,14 +430,6 @@ factorial(5); // == 120
 ### User-defined literals for standard library types
 New user-defined literals for standard library types, including new built-in literals for `chrono` and `basic_string`. These can be `constexpr` meaning they can be used at compile-time. Some uses for these literals include compile-time integer parsing, binary literals, and imaginary number literals.
 ```c++
-constexpr int operator"" _test(unsigned long long x) {
-  return 0;
-}
-123_test; // == 0
-```
-
-Built in literals for `chrono`:
-```c++
 using namespace std::chrono_literals;
 auto day = 24h;
 day.count(); // == 24