Integrate interactive training loop from Nick

[chengxuz]

@nhaber

• Make sure the optimizer is able to handle multiple losses
• DBinterface, when things will be saved in the database
• Dataset creation, graph instantiation can be done flexibly

[yamins81]

@nhaber @ewang314 @khkim1 @mjlbach Is this basically done? How do the efforts that you guys have been working on relate to this issue?