arrow

ARROW-13296: [C++] Provide a reflection compatible enum replacement

Provides an enum replacement with minimal reflection capabilities. These can be declared by inheriting from a helper with CRTP, including a static string literal data member containing the enum's values:

```c++
struct Color : EnumType<Color> {
  using EnumType::EnumType;
  static constexpr char* kValues = "red green blue";
};
```

Values of enumerations declared in this way can be constructed from their string representations at compile time, and can be converted to their string representation for easier debugging/logging/and less repetitive boilerplate in the bindings and elsewhere mapping to/from user provided string values.

For example:
```c++
int get_hex_value() {
    std::string input;
    std::cin >> input;
    switch (*Color(repr)) {
      case *Color("red"):
        return 0xff0000;
      case *Color("green"):
        return 0x00ff00;
      case *Color("blue"):
        return 0x0000ff;
      default:
        std::cout << "Don't know that one; input hex value\n";
        std::cin >> std::hex >> input;
        return std::stoi(input);
    }
}
```

Closes #10691 from bkietz/13296-Provide-reflection-compat

Authored-by: Benjamin Kietzman <bengilgit@gmail.com>
Signed-off-by: David Li <li.davidm96@gmail.com>