Add reaction to a post containing specified text [DO NOT SUBMIT]

[reharri7]

We'd like to add certain reactions to posts that contain predefined text. Let's add a function that listens to a dictionary, set, map (whatever key value pairs are called in Rust). The function will look for the text in the keys and send a reaction with the matching value. We will be able to add reactions to the key value data structure and reuse the function

[jsontm]

Use the ping command as a reference and build your response using the reactions.add API.

[jsontm]

This is going to be a tutorial issue to help people on-board. Everyone new to the project should try to set up their dev environment and then submit a pull request for this issue. We will not merge any of them into main, but I can review and help people understand the project more this way.