remove exit-tree, add exitBalance and accHash in state

[krlosMata]

This PR does the following:

• updates circuits to remove the exit-tree
• add accumulatedHash and exitBalance
• add option to extend circom to debug properly and reuse compiled circuits

Update circuits summary

balance-updater

• add computing exitBalance for receiver leaf if transaction is an exit
• remove unnecessary signal isP2Nop

decode-tx

• add computation of L1L2TxsData in integer

fee-tx

• update leaf with exitBlance and accumulatedHash

hash-inputs

• remove exitRoot

rollup-main

• remove intermnediary signal imExitRoot
• remove newExit flag
• remove signals for inserts on Processor2: isOld0_2, oldKey2 & oldValue2
• add new state fields: exitBalance & accumulatedHash
• L1L2TxsData is 0 if transaction is onChain

rollup-tx-states

• remove insertions on processor2
• update processor2 functions

rollup-tx

• compute accumulated hash
• remove selectors when processor2 was performing an insert
• remove exit root computation

Extend circom

• npm run extend-circom will add extra functionality to circom in order to debug circuits
• reuse and pathTmp should be set correctly if a circuit wants to be reused

close #38

[laisolizq]

😸

[invocamanman]

typo

[invocamanman]

great! ^^