The function `array.reverse` takes an array as an argument, and returns an array with a reversed order of elements.
The function `strings.reverse` takes a string as an argument, and returns a string with a reversed order of unicode code points.
WASM support is included for both built-ins.
Fixes#3736
Signed-off-by: Kristian Svalland <kristian.svalland@gmail.com>