* [DEV-303] Implement block finality
* [DEV-303] Add finality tests
* [DEV-303] Make finality tests use maybeAcceptBlock
* [DEV-303] Only check finality rules if we are fastAdd mode
* [DEV-303] replace hasBiggerFinalityScoreThan checks with .finalityScore()
* [DEV-308] Enforce tx order in block to be by sub-network ID
* [DEV-308] Use mutable block in TestCheckBlockSanity
* [DEV-308] Fixed comment
* [DEV-308] Fixed TestCheckBlockSanity: use invalid block instead of modifying good block
* [DEV-308] Changed name of block in TestCheckBlockSanity
* [DEV-255] create checkConnectToPastUTXO and move the required functionalities to it from checkConnectBlock
* [DEV-255] get rid of checkConnectBlock
* [DEV-255] rename pNode -> node
* [DEV-255] add comment to describe ErrWithDiff