Add missing feature in update

• pmin (done)
• continuous -> clusterization heuristics (done)
• start-up costs (done)
• H2 lt-storages (prepare for WV update)
  • validate lt storages policy (Arnaud or Juliette)
  • improve the workaround of rounding issue
• H2 imports
  • improve implentation (config, handling of maximports)
• study parameters (mcYears, accurate, start-date ...)
• output deletion
• Check if pmin requieres accurate and/or must-run