Feature: @LearnMore annotation

[dylanirlbeck]

Per this thread on the forum, I'm wondering if this annotation is available for use? If not, what would the required work to implement it?

We're looking to use this annotation to attach articles in the story-based/ethics problems we're building. cc @harsh183 @migujorg

[harsh183]

On a similar note, would a @SimilarProblems annotation be useful. Like let's say someone really struggled with a Sets problem, then after they're done it can point them to more practice problems.