Remove before_transform and after_transform and allow more PyTorch lightning like hooks (that interfere execution process) and TransformTemplate

[hmirin]

• Hooks are a legacy of old implementations that allow jumps etc...

• Now, that isn't good because:

  • the order of execution is obscured by the existence of hooks. rendering and hooks are somewhat duplicated ideas because both may transform data. It adds just complexity.

• We should add TransformTemplate

• The importance is user should find it easy to grasp the logic.

• The transform is like Keras's one. That can be combined as a layer. We should make such a thing.

• PyTorch Lightning-like hooks are not like the current implementation.

  • That should be: record every template execution to remote such as w&b
  • We should make such hooks to enable the logging feature.

• We should also remove the need to template_id (because some of it is required by jump feature)