Update README.md

Update conda envs (#268)

Update osx.yml

Update cpu.yml

Delete conda_env/cuda102.yml

Update and rename cuda113.yml to cuda118.yml

Update and rename cuda123.yml to cuda121.yml

Update cuda123.yml

Update cuda123.yml

Update cuda123.yml

Create cuda123.yml

Update splitter.py

Update iQSPR.ipynb (#265)

Fix typos

Add demo for element substitution CSP