TransactionInBlock crashed if json was nil and there was an error
because it tried to access fields `From` and `BlockHash` of the nil object.

* core/signer, clef: improve ui-test flow, fix errors in uint handling for eip-712

* core/signer: add fuzzer testcases + crashfixes

* signer: address review concerns, check sign in integer parsing

* accounts/scwallet: Add a switch to enable smartcard support

* accounts: change the meaning of the switch

* disable card support in windows until tested
* only activate account if pcscd socket file is present
* the switch is now the path to the socket file

* accounts/scwallet: holiman's review feedback

* accounts/scwallet: send the path to go-pcsclite

* accounts/scwallet: add default, per platform path

* accounts/scwallet: fix error log warning

* accounts/scwallet: update pcsc lib to latest

* accounts/scwallet: use default path from pcsclite

* scwallet: forgot to change switch name

* cmd: minor style cleanups (error handling first, then happy path)

les, les/flowcontrol: implement LES/3

* Update codeowners

* Add karalabe to clique

* remove codeowner for consensus/clique

* Removed comment section referring to Cloudflare's bn curve parameters

* Added comment to clarify the nature of the parameters

* Changed value of xi to i+9

internal/build: fix Travis and AppVeyor commit string injection

vendor: update go-duktape to v2.3.0

accounts/scwallet: Display PUK retry count

* core: reinit chain from freezer in batches

* core/rawdb: concurrent database reinit from freezer dump

* core/rawdb: reinit from freezer in sequential order

Without this, accounts/keystore fails to build for Darwin with
CGO_ENABLED=0.

core/rawdb: keep genesis in key-value store for full sync too

* eth, les: reject light client connection is server is not synced

* eth, les: rename function and variables

* les: format

* p2p: remove direct import of cgo-library

* accounts, rpc: more nocgo alternatives

* rpc: move unix path constant into separate file

* accounts/scwallet: address review concerns, remove copy-pasta

* Added checks for nil pointers in Marshal functions

* Set nil pointer to identity in GT before marshaling

* tests: make transaction tests run again, fix #19033

* tests: refactor transaction tests

* log: Do not pad too long values

* log: gofmt

* les: avoid fetcher deadlock on requestChn

core/rawdb, eth/downloader: align 64bit atomic fields

* build: disable swarm packages

* build: remove allCrossCompiledArchiveFiles; inline allToolsArchiveFiles

* build: get rid of some superfluous comments