Create Storage to open connection to MongoDB.
Use storage solution from Tsuru.
Add `errors` package. For now there is just a ValidationError.
Change the way we use default values to connect to MongoDB.
Add `Service` with "Create", "Delete"and "Count" methods.
Add Makefile with `test` command for now.
Rename "storage" package to "db".
Remove unnecessary code.
Refactor package name to app.
Add `User` with "CreateUser" and "DeleteUser" methods.
Add missing `defer conn.Close()`, "FindUserByUsername" and "HashPassword".
Remove created user after test.
Stop droping the database after tests. It's pretty slow.
Remove User from database after test.
Use `User.Password` as string.
Add Owner property to Service".
Add space.
Add "Group" with "CreateGroup" and "DeleteGroupByName" methods.
Add "FindGroupByName" method and some refactoring.
Add "AddUsers" and "containsUser" methods to `Group`.