Changing 202 responses to 200 because Mobile Commons mDatas will treat them as errors
Implemented user progression from one story node to the next
Tracks user responses to each node of a story in the database
Creating a single mongo connection that models get created off of
Merge pull request #75 from jonuy/issue-74

Creating a single mongo connection that models get created off of
Merge pull request #72 from jonuy/story-progression

Basic story progression