Dataset Processing Nodes and Improved LoRA Trainer Nodes with multi resolution supports. (comfyanonymous#10708)

* Create nodes_dataset.py

* Add encoded dataset caching mechanism

* make training node to work with our dataset system

* allow trainer node to get different resolution dataset

* move all dataset related implementation to nodes_dataset

* Rewrite dataset system with new io schema

* Rewrite training system with new io schema

* add ui pbar

* Add outputs' id/name

* Fix bad id/naming

* use single process instead of input list when no need

* fix wrong output_list flag

* use torch.load/save and fix bad behaviors

Author: KohakuBlueleaf