v3.0.0 - Support indexing via events for L2 networks

• Support v1.3.0 contracts. If L2 version of the contracts is used for a Safe, events indexing is possible and a tracing node is not required anymore (#255)
• Fix S3 image uploading
• Remove deprecated web3 methods
• Update dependencies
• Support polygon network (#264)
• Remove new txs on master copy update (#262)
• Fix admin search
• Fix tx not found when indexing
• Emulate ether transfers for Safe events indexer
• Make gas error estimation more friendly for clients
• Rename NodeConectionError -> NodeConectionException
• Fix issue with duplicated contract abis
• Search safe_tx_hash on MultisigTransaction admin
• Update response for ethereum checksum validation errors
• Fix firebase token invalidation
• Fix infinite loop on process decoded transactions
• Refactor reindex method
• Add method to parse multisig transaction signatures
• Optimize trace_block indexer
• Add new filters to transfers endpoint
• Fix sourcify issues
• Add order by modified for multisig-transactions endpoint
• Update Transaction modified when a confirmation is added