Added maintainers wanted. Removed slack link.
Added maintainers wanted. Removed slack link.

We need new maintainers, as we can no longer devote the time necessary to NML.
nylas-mail-lives/nylas-mail,nylas-mail-lives/nylas-mail,nirmit/nylas-mail,nirmit/nylas-mail,nylas-mail-lives/nylas-mail,nylas-mail-lives/nylas-mail,nirmit/nylas-mail,nylas-mail-lives/nylas-mail,nirmit/nylas-mail,nirmit/nylas-mail