fix demo simple interface, issues with imports, bump to 1.0.2

[WilsonGregory]

Changes

• fix imports in other_models, vae_models
• simplify imports in DemoSimpleInterface notebook now that its on pip
• fix an issue in train model where if the validation set is empty, EarlyStopping on val_loss causes issues. So now it only does early stopping if there is a validation set

Testing

• Ran demo simple interface
• ran a few other notebooks that I have locally

[beelze-b]

Looks mostly alright to me. I just had two questions.