Add klay_getTotalSupply API

[blukat29]

Proposed changes

• Add reward.GetTotalReward(num) -> <Minted, BurntFee> which is a lightweight version of reward.GetBlockReward that only returns the total minted and burnt amounts, oblivious of validator staking amounts.
• Add DB schema AccRewards where

   db.ReadAccRewards(num) = <AccMinted(num), AccBurntFee(num)>
       AccMinted(num) = GenesisTotalSupply + sum(GetTotalReward(x).Minted for x in [1, num])
       AccBurntFee(num) = sum(GetTotalReward(x).BurntFee for x in [1, num])

• Add the reward.SupplyManager object that maintains AccTotalRewards up to the latest block.
• Add RPC klay_getTotalSupply(num)

  klay_getTotalSupply(num) = {
      "totalSupply": totalMinted - totalBurnt,
      "totalMinted": AccMinted(num),
      "totalBurnt": (sum of the below),
      "burntFee": AccBurntFee(num),
      "zeroBurn": State(num).GetBalance("0x0"),  # unsupported in Cypress, but return anyway because it's de-facto standard burn address in other chains
      "deadBurn": State(num).GetBalance("0xdead"),  # another de-facto standard burn address
      "kip103Burn": State("latest").Kip103Addr.memo.burnt,   # only if num >= Kip103Block
      "kip160Burn": State("latest").Kip160Addr.memo.burnt,   # only if num >= Kip160Block
  }

Cypress example

> klay.getTotalSupply('latest')
{
  burntFee: "0x28ee933736fa159f39364",
  deadBurn: "0x40bea489f3f8944d93efbd",
  kip103Burn: "0x111d0449fb2a238eca3b1720",
  kip160Burn: "0x0",
  totalBurnt: "0x116051d7b8918bc471c29a41",
  totalMinted: "0x24971a118ccfd6cbe4800000",
  totalSupply: "0x1336c839d43e4b0772bd65bf",
  zeroBurn: "0x0"
}

Types of changes

Please put an x in the boxes related to your change.

• Bugfix
• New feature or enhancement
• Others

Checklist

Put an x in the boxes that apply. You can also fill these out after creating the PR. If you're unsure about any of them, don't hesitate to ask. We're here to help! This is simply a reminder of what we are going to look for before merging your code.

• I have read the CONTRIBUTING GUIDELINES doc
• I have signed the CLA
• Lint and unit tests pass locally with my changes ($ make test)
• I have added tests that prove my fix is effective or that my feature works
• I have added necessary documentation (if appropriate)
• Any dependent changes have been merged and published in downstream modules

Related issues

• Implementing getTotalBurnt, getTotalCirculatingSupply API  #1617

Further comments

• In an instacne with warmed-up EBS volume, it took around 3 hours to accumulate rewards from block 0 to 153,600,000.
• It's much slower in a cold EBS because of the time reading historic blocks.