Efficiency Nodes for ComfyUI

UPDATES/CHANGES:

• Added Control Net support to the 'Efficient Loader' and 'XY Plot' nodes via the new 'Control Net Stacker' node.

• 4 NEW XY Plot input nodes. 'Add/Return Noise', 'Start at Step', 'End at Step', and 'Control Net Strenghts'.

• New KSampler Adv. (Efficient) node.

• The "preview_image" input from the Efficient KSampler's has been deprecated, its been replaced by inputs "preview_method" & "vae_decode".
  The new Efficient KSampler's "preview_method" input temporarily overrides the global preview setting set by the ComfyUI manager.

• Several XY Plot input nodes have been revamped for better XY Plot setup efficiency.

Extras:

• Enable hot-reload of XY Plot lora, checkpoint, sampler, scheduler, vae via the ComfyUI refresh button.

• Upgraded the auto installation of required packages from requirements.txt.