Finished register.

src/snek/service/user.py

@@ -1,13 +1,14 @@
 from snek.system.service import BaseService 
 from snek.system import security 
 
-class UserService:
+class UserService(BaseService):
     mapper_name = "user"
 
-    async def create_user(self, username, password):
+    async def register(self, email, username, password):
         if await self.exists(username=username):
             raise Exception("User already exists.")
         model = await self.new()
+        model.email = email
         model.username = username
         model.password = await security.hash(password)
         if await self.save(model):