Consider adding a greet bot

[dpliakos]

With the number of our members increasing, it would be a good idea to add a greet bot to our slack account. This greet bot good help with the on boarding process .

We should add some greeting, our code of conduct and some useful links.

[dpliakos]

I recently added one to another slack workspace, this is the result (note that the links are not all active yet)

References https://greet.bot/