Octal literals are not allowed in strict mode

[WilliamHuey]

In the index.js, of this module, the octal literal is causing an error in 'strict' mode. I encounter this error when using babel and webpack to compile js output.

If all the '\033' were replaced with the hex equivalent, '\x1B', as shown in this repository: https://github.com/stevenvachon/cli-clear/commit/e6458ee26f18fa1f87601297d595ea7e2aa6e81d, the error will go away.

Thanks. 😃