Validation: block

[supiket]

Noting that invalidity is transitive, i.e. a seemingly valid block that is the child of an invalid block is invalid, validate that:

• Hash(parent) points to an actual block
• Block number is sequential
• Block height is sequential
• Gas limit below a certain limit
• Size in bytes is below a certain limit
• Timestamp of block >= timestamp of parent
• Block state contract solution is the first solution
  • The order in the solution data does not matter. A block that consists of one solution is valid as long as the block state contract solution is part of that solution.