Resume opencv4nodejs

Hello @UrielCh @pdiaz @arvind-india @longtp12 @alalialisiong @Misoss @jeffreycrow @koush @stoefln @ogibor @kokarn @ht-jo @GM-Alex @aiham @Snusmumr1000 @ben60523 @mfukushim @Profab @sugumura @zegami @pck886 @ewanharris @psiservices-soriley

You may have noticed that the opencv4nodejs project is no longer maintained since 2 years, this is because @justadudewhohacks do not have enough time right, which we all understand.

I see on github that a lot of forks have been maintained during last months, and I'm afraid the forks will diverge too much, leaving the new comers in a difficult situation.

If you are interested to discusss this, i have open a channel `#opencv4nodejs` in the opencv.org slack.
Please connect to the slack using [this link](https://join.slack.com/t/open-cv/shared_invite/zt-59r70dt1-iG2WZ3gG2WbnMnGZEYfcSQ) and then join the discussion by connecting to the `#opencv4nodejs` channel.

Thanks for your help