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[case-eee]

@s-espinosa

this PR does the following

• adds tests for the Joke model
• adds .random and #full to Joke to pull a random joke and to concatenate the question and answer of a particular joke
• adds .scope? to the User model to grab all the active users
• adds a rake task that sends a random joke to every active user

questions for you:

• how will we keep track of which user's received which jokes? do we want to control for that? currently, it's completely random so a user could receive the same joke two days in a row
• is this the best way to structure the rake task? can you think of any better way?

[case-eee]

@s-espinosa made a bunch of updates here - add the JokeUser table, add associations, modify our TwilioMessage.send method to accept a joke, records a JokeUser every time a Joke is sent

let me know what you think 🎉