New home for MESS

[hatemhelal]

Quite a few somewhat unrelated updates to the MESS project:

• fixed parsing of the MESS_ENABLE_FP64 variable
• updated pre-commit checks
• removed the graphcore copyright lint check
• Added a method for generating a cubic lattice of Hydrogen atoms (aimed to be used in scaling benchmarks)
• Support max_steps, 'atol', and 'rtol' in the minimise APIs
• Removing source level copyright notices and updated license