Motivation for this change

Upstream maintenance release
Most notably fixes some regressions related to hardware wallets on Darwin

Quote from upstream:

This release enables the Byzantium hard fork transition at block number 4370000 (~17th October) on the mainnet and block number 1035301 (~9th October) on the Rinkeby test network. Please update well before these dates to ensure a smooth transition.

Things done

• Tested using sandboxing (nix.useSandbox on NixOS, or option build-use-sandbox in nix.conf on non-NixOS)
• Built on platform(s)
  • NixOS
  • macOS
  • Linux
• Tested via one or more NixOS test(s) if existing and applicable for the change (look inside nixos/tests)
• Tested compilation of all pkgs that depend on this change using nix-shell -p nox --run "nox-review wip"
• Tested execution of all binary files (usually in ./result/bin/)
• Fits CONTRIBUTING.md.