Implement accelerate/cancel feature for eth based transactions

[mNizhurin]

When transaction is stuck in pending state, user might need to rebroadcast it with same or higher fee.
User can accelerate only one oldest pending transaction

related issues:
horizontalsystems/ethereum-kit-android#132
horizontalsystems/ethereum-kit-android#131
horizontalsystems/ethereum-kit-android#130

ex. of drop-replaced tx: https://etherscan.io/tx/0xa59d1da57e80aee221ea3aea6ea5f5dd71850d9505ad1554090fa871ed288759

[esengulov]

UI / UX guidelines:

• SpeedUp and Cancel buttons should appear in TX info, only for pending transactions
• SpeedUp and Cancel buttons should appear on all TX types (send, approve, contract call except SWAP transaction types)
• the client should double recheck status of the pending TX when user clicks on Cancel/SpeedUp buttons.
  -- let user proceed to confirm screen only if original TX still pending.
  -- If transaction has been confirmed then show following UI alert (This transaction has been already confirmed and can no longer be accelerated or cancelled.) with OK button.
• SpeedUp option uses same transaction and same nonce, but with higher fee
• Cancel option creates new empty transaction to self and same nonce, but with higher fee
• On speedup/cancel confirmation screens, the client should again check the status of original TX and let user proceed only if TX is pending
• @Dianaaiym add info texts to both speedup/cancel screens. These texts will explain the purpose/terms of the transaction to the sender.

[TalgatNurdinov]

https://www.figma.com/file/M9MoqHabdQCdu2a9pIEo5N/v.-2.0-Unstoppable-Design-System?node-id=39764%3A320096

[esengulov]

@omurovch @Dianaaiym

• update info texts for speedup / cancel controllers

SpeedUp

This action will attempt to invalidate previous transaction by resending it with a higher fee. If the original transaction remains pending when a new one sent there is s a high chance (not guaranteed) that it will be invalidated and replaced. Only one of these two transactions will be included in the blockchain.

Cancel

This action will attempt to invalidate previous transaction by resending as a 0 value transaction to self. If the original transaction remains pending when a new one sent there is s a high chance (not guaranteed) that it will be invalidated and replaced. Only one of these two transactions will be included in the blockchain.