[Docs] Add a section about joining the Core Team
[Docs] Add a section about joining the Core Team

tdeo/rubocop,bbatsov/rubocop,rrosenblum/rubocop,rrosenblum/rubocop,rrosenblum/rubocop,tdeo/rubocop,maxjacobson/rubocop,maxjacobson/rubocop,tejasbubane/rubocop,tdeo/rubocop,bbatsov/rubocop,tejasbubane/rubocop,maxjacobson/rubocop,tejasbubane/rubocop