Add Welcome Bot to create an inclusive environment for new contributors

[Tlazypanda]

Is your feature request related to a problem? Please describe.
Welcome is a simple way to welcome new users based off maintainer defined comments.

The 3 plugins it combines with are new-issue-welcome(Comment to be posted to on first time issues) , new-pr-welcome(Comment to be posted to on PRs from first time contributors in your repository) and first-pr-merge(Comment to be posted to on pull requests merged by a first time user).

Describe the solution you'd like
We can setup Welcome bot by adding the GitHub App to our organization repositories and configuring .github/config.yml according to the content of the messages we want.

This will make the new contributors feel welcomed and at ease in interacting with the community.

Additional context
Screenshots that depict the Welcome bot in action:

[Tlazypanda]

Hey @abhineet97 @kaskou Just adding this issue since this bot needs to be setup in other repositories as per discussion with @gmajan 😅 Thanks ✌️

[abhineet97]

Hi @Tlazypanda

Thanks for the creating the issue.

Guessing that this is the discussion that you're talking about, I wanted to suggest that how about you make all the necessary changes in the Import-Me repo and then after you're done, we can pull all the changes from there. This way nobody would have to commit the same thing again and again.

Please let me know what you think.

[Tlazypanda]

@abhineet97 That's a great idea!! This has already been setup in the Import-me repo 😅 It is good that we made an issue here atleast we can track back later ✌️