message: Remove the check that enforce first block in UAHF (Aug 1st, 2017) is bigger than 1MB
  Since block 0x000000000000000000651ef99cb9fcbe0dadde1d424bd9f15ff20136191a5eec
  is buried undera 19 months of PoW and 4 checkpoints we don't need to
  check if the first block in UAHF chain is bigger than 1MB.
diff: @@ -1408,24 +1408,6 @@ bool ContextualCheckBlock(const CBlock &block,
  }
  }
  - // UAHF enforce that the fork block is > 1MB
  - // (note subsequent blocks can be <= 1MB...)
  - // An exception is added -- if the fork block is block 1 then it can be <= 1MB. This allows test chains to
  - // fork without having to create a large block so long as the fork time is in the past.
  - // TODO: check if we can remove the second conditions since on regtest uahHeight is 0
  - if (pindexPrev && UAHFforkAtNextBlock(pindexPrev->nHeight) && (pindexPrev->nHeight > 1))
  - {
  - DbgAssert(block.GetBlockSize(), );
  - if (block.GetBlockSize() <= BLOCKSTREAM_CORE_MAX_BLOCK_SIZE)
  - {
  - uint256 hash = block.GetHash();
  - return state.DoS(100,
  - error("%s: UAHF fork block (%s, height %d) must exceed %d, but this block is %d bytes", __func__,
  - hash.ToString(), nHeight, BLOCKSTREAM_CORE_MAX_BLOCK_SIZE, block.GetBlockSize()),
  - REJECT_INVALID, "bad-blk-too-small");
  - }
  - }
  -
  CBlockIndex indexDummy(block);
  indexDummy.pprev = pindexPrev;
  indexDummy.nHeight = pindexPrev == nullptr ? 1 : pindexPrev->nHeight + 1;
  