ChaiScript language highlighting support

Language
Easy to use embedded scripting language for C++.

Additional resources
http://chaiscript.com
http://chaiscript.com/examples.html#ChaiScript_Language_Examples
https://github.com/ChaiScript/ChaiScript/blob/develop/cheatsheet.md#language-reference
https://codedocs.xyz/ChaiScript/ChaiScript/LangGettingStarted.html
https://codedocs.xyz/ChaiScript/ChaiScript/LangObjectSystemRef.html
https://codedocs.xyz/ChaiScript/ChaiScript/LangStandardLibraryRef.html
https://codedocs.xyz/ChaiScript/ChaiScript/LangKeywordRef.html
https://rawgit.com/libretro/libretro-chailove/docs/index.html
https://rawgit.com/libretro/libretro-chailove/docs/namespacelove.html