Add compel node and conditioning field type

[StAlKeR7779]

Done as I said in title, but need to test(and understand) how cli works, as previously it uses single prompt and now it's positive and negative.

[blessedcoolant]

Works as advertised.

But I think we need to change a few things unrelated to this PR.

1. Get a model loader node in which outputs three values - Text Encoder, UNet, VAE
2. Feed the Text Encoder to the Compel Node instead of the Model
3. Feed the UNet to the Text To Latent instead of Model
4. Feed the VAE to the Latent instead of the Model

[damian0815]

thanks, looks good. not sure the latents storage is the right place to put the embeddings tho

[Kyle0654]

Some questions and comments about usability. Try using it in the CLI to validate usability =)

[blessedcoolant]

Functionality is good. But why did you merge both Positive and Negative conditioning into the same output? I think they should both be outputted as individual outputs so they can be plugged as needed across multiple nodes if need be.