Add color support in web console.

[Et7f3]

In ocsigen/js_of_ocaml#928 is_tty return false when used in browser, thus pastel doesn't output color in web console.

Chrome can use ansi color . I have opened a issue in caniuse repo to see if it is widely supported.

A other approch is to use css in console. Examples can be found in this SO thread or in Facebook/Discord website web openning dev tool. From SO css support is support from a long time in firefox and also supported in chrome.

[bandersongit]

I'm very interested to see what the broader browser support is. In the short term you could have some custom logic to check for Chrome and use Pastel.setMode(Pastel.Terminal) to override the mode that Pastel detects by default