We probably need to add some methods to the APIClient to allow people to do common things easily without having to formulate a get or post request on their own. I started off with a method to retrieve groups for the current user which returns an array of model objects. I created a model object called YMGroup and I tried using Mantle to handle the JSON deserialization.

Going forward I think we need to add API methods to return feeds (algo, groups, following, etc), joining, following, liking, replying and user related stuff as well.

I'm not sure whether this PR should actually be merged, but I thought it would do a good job of illustrating one approach we can take.