Refactor event processing

[aminlatifi]

Bridge monitor should process Waiting events ordered by time events are emitted, but currently we order them by blocknumber.
As events are fetched from two different chains, blocknumber value is not the correct field to order events based on. This causes events not be processed in order and failure in some procedures.

To understand what issue could happen, donate and withdraw actions each have two events which should be processed in order and be matched to each other. One in home network (mainnet) and one in foreign network (rinkeby).
Reliance on blocknumber field may cause processing second event first.

[mohammadranjbarz]

Bridge monitor should process Waiting events ordered by time events are emitted, but currently we order them by blocknumber.
As events are fetched from two different chains, blocknumber value is not the correct field to order events based on. This causes events not be processed in order and failure in some procedures.

To understand what issue could happen, donate and withdraw actions each have two events which should be processed in order and be matched to each other. One in home network (mainnet) and one in foreign network (rinkeby).
Reliance on blocknumber field may cause processing second event first.

@aminlatifi could you give me permission to push branch in this repository