Changed so that the id of a user is the same as the username.
Changed from searching for username to getting a doc with username
Forgot to change from search to get when deleting user
Couldn't create a user with a name that already existed, just had to change a name in the tests
Fixed more with the username in datapoints
Made sure to make the user string to lowercase
Merge pull request #188 from projectcs13/Sp7.Sc1.username_should_be_id

The id of a user should be the username