upgrade state-root

[krlosMata]

Write specification and implementation regarding how to manage proporly the state root upgrade.

First draft

• Stop rollup features until root is fully upgraded
• Add function updateRoot which should be called N times, depending on current account numbers and maximum accocunt that the circuit can handle
• add necessary information in events, so data could be synchronized
• increase batch number by 1, which would set the updateBatchNumber
• maintain old functionalities if batch number is < updateBatchNumber

[krlosMata]

Summary specification: https://hackmd.io/moApdQkDRBmeBQAF_dQwBw