Chroma fp8 e5m2

Quantizer from the model provided by Phr00t in huggingface - https://huggingface.co/Phr00t/Chroma-Rapid-AIO

Use a CFG of 1, 8 steps and sa_solver sampler with the beta scheduler (V3). However, the "ipndm" sampler gives good results too, particularly more realistic ones.