Co-authored-by: Pascal Dierich <pascal@pascaldierich.com>

* Named functions and defined a basic EIP191 content type list

* Written basic content type functions

* Added ecRecover method in the clef api

* Updated the extapi changelog and addded indications in the README

* Changed the version of the external API

* Added tests for 0x45

* Implementing UnmarshalJSON() for TypedData

* Working on TypedData

* Solved the auditlog issue

* Changed method to signTypedData

* Changed mimes and implemented the 'encodeType' function for EIP-712

* Polished docstrings, ran goimports and swapped fmt.Errorf with errors.New where possible

* Drafted recursive encodeData

* Ran goimports and gofmt

* Drafted first version of EIP-712, including tests

* Temporarily switched to using common.Address in tests

* Drafted text/validator and and rewritten []byte as hexutil.Bytes

* Solved stringified address encoding issue

* Changed the property type required by signData from bytes to interface{}

* Fixed bugs in 'data/typed' signs

* Brought legal warning back after temporarily disabling it for development

* Added example RPC calls for account_signData and account_signTypedData

* Named functions and defined a basic EIP191 content type list

* Written basic content type functions

* Added ecRecover method in the clef api

* Updated the extapi changelog and addded indications in the README

* Added tests for 0x45

* Implementing UnmarshalJSON() for TypedData

* Working on TypedData

* Solved the auditlog issue

* Changed method to signTypedData

* Changed mimes and implemented the 'encodeType' function for EIP-712

* Polished docstrings, ran goimports and swapped fmt.Errorf with errors.New where possible

* Drafted recursive encodeData

* Ran goimports and gofmt

* Drafted first version of EIP-712, including tests

* Temporarily switched to using common.Address in tests

* Drafted text/validator and and rewritten []byte as hexutil.Bytes

* Solved stringified address encoding issue

* Changed the property type required by signData from bytes to interface{}

* Fixed bugs in 'data/typed' signs

* Brought legal warning back after temporarily disabling it for development

* Added example RPC calls for account_signData and account_signTypedData

* Polished and fixed PR

* Polished and fixed PR

* Solved malformed data panics and also wrote tests

* Solved malformed data panics and also wrote tests

* Added alphabetical sorting to type dependencies

* Added alphabetical sorting to type dependencies

* Added pretty print to data/typed UI

* Added pretty print to data/typed UI

* signer: more tests for typed data

* signer: more tests for typed data

* Fixed TestMalformedData4 errors and renamed IsValid to Validate

* Fixed TestMalformedData4 errors and renamed IsValid to Validate

* Fixed more new failing tests and deanonymised some functions

* Fixed more new failing tests and deanonymised some functions

* Added types to EIP712 output in cliui

* Added types to EIP712 output in cliui

* Fixed regexp issues

* Fixed regexp issues

* Added pseudo-failing test

* Added pseudo-failing test

* Fixed false positive test

* Fixed false positive test

* Added PrettyPrint method

* Added PrettyPrint method

* signer: refactor formatting and UI

* signer: make ui use new message format for signing

* Fixed breaking changes

* Fixed rules_test failing test

* Added extra regexp for reference types

* signer: more hard types

* Fixed failing test, formatted files

* signer: use golang/x keccak

* Fixed goimports error

* clef, signer: address some review concerns

* Implemented latest recommendations

* Fixed comments and uintint256 issue

* accounts, signer: fix mimetypes, add interface to sign data with passphrase

* signer, accounts: remove duplicated code, pass hash preimages to signing

* signer: prevent panic in type assertions, make cliui print rawdata as quotable-safe

* signer: linter fixes, remove deprecated crypto dependency

* accounts: fix goimport

* accounts, eth, clique: implement external backend + move sighash calc to backend

* signer: implement account_Version on external API

* accounts/external: enable ipc, add copyright

* accounts, internal, signer: formatting

* node: go fmt

* flags: disallow --dev in combo with --externalsigner

* accounts: remove clique-specific signing method, replace with more generic

* accounts, consensus: formatting + fix error in tests

* signer/core: remove (test-) import cycle

* clique: remove unused import

* accounts: remove CliqueHash and avoid dependency on package crypto

* consensus/clique: unduplicate header encoding

* accounts/keystore: reduce file name length

* accounts/keystore: reduce code line width