Add ArkScript language

## Language name
[ArkScript](https://github.com/ArkScript-lang/Ark)

## URL of example repository

Examples are hosted here: https://github.com/ArkScript-lang/Ark/tree/dev/examples

Also here (the standard library) https://github.com/ArkScript-lang/std

## URL of syntax highlighting grammar

A basic highlighting syntax is available here: https://github.com/ArkScript-lang/ArkScript-VSC/blob/master/syntaxes/arkscript.tmLanguage.json

## Most popular extensions

The single extension used for the language is `.ark`; others, such as `.arkm` (an ArkScript module, compiled as a DLL/SO/DYNLIB) or `.arkc` (ArkScript compiled file, a bytecode), are not meant to be published and can not be highlighted (because they are binary files).

## Detected language

`.ark` is in ArkScript