New Rollmint Header

[nashqueue]

Depends on #574
Needs Discussion with Leadership

Known issues with header:

• Decide on type of height related fields #688
• Use consistent type for all hash fields in Header #689
• Consider removing NamespaceID from header #690

Additional features needed:

• Implement Header interface #641
• Add Merkle root over all transactions to block header #580
• Add Merkle root over all intermediate state roots to block header, current Datahash is final ISR #581
• Save DA blob commitment of previous block to block header #582
• Create ADR to generalize header and block format #583
• Verify validity of state root provided in block fraud proof #440