Refactoring db logic into service layer. Remove db refs in main.go
Remove Database init in api
Add HandleIsUnique service
Add EmailIsUnique service
Add NewUser service
Add MakeDefaultCirclesFor; CreateNewUser ported
Update authenticate and add GoodUserCredentials
Port session stuff to service
Utilize service in Login and NewCircle
Adjust tests to pass under service related changes
Merge branch 'service-layer'

Conflicts:
	go/src/api/api.go
	go/src/test/api_test.go