Availability via Packagist.org (Composer)

[marclaporte]

It would be great if this lib could be available here:
https://packagist.org/search/?tags=jmap

FYI, here is the story of another code base for PHP/JMAP/Composer:
cypht-org/cypht#311

[marclaporte]

https://packagist.org/packages/jason-munro/cypht now has over 55 000 downloads.

@barnslig Any chance we could do this here as well?

Thanks!