Add cache logic for `Make_cached_carbonated_map`

Wait for !17 (merged). Please review from f0a3e5d3

This MR add cache logic for Make_cached_carbonated_map. In order to review it, please check every storage accessor/updater has following properties

∆ : an in-memory cache

δ : an in-storage cache

• mem
  • Miss ∆ Miss δ
    • should we update both ∆ + δ here?
    • consume mem gas
  • Miss ∆ Hit δ
    • no gas consumption
• get
  • Miss ∆ Miss δ
    • Update ∆ + δ
    • consume read gas
  • Miss ∆ Hit δ
    • Update ∆
    • no gas consumption
• find
  • Miss ∆ Miss δ
    • Update ∆ + δ
    • consume read gas
  • Miss ∆ Hit δ
    • Update ∆
    • no gas consumption
• update
  • Update ∆ + δ
  • consume write gas
• init
  • Update ∆ + δ
  • consume write gas
• add
  • Update ∆ + δ
  • consume write gas
• remove
  • Remove ∆ + δ
  • consume remove gas
• remove_existing
  • Remove ∆ + δ
  • consume remove gas
• add_or_remove (same as add or remove)