Fix localhost builds

Dependencies

• [2] YVFKZFAP Fix build
• [3] H46LUUZY hydra-queue-runner: don't try to distribute builds on localhost
• [4] YSZQ3ORR Fix build
• [5] EBJP3MNA Build against nix-master
• [6] WV4SSAIY Build against nix-master
• [7] 5AIYUMTB Basic remote building
• [8] BYVRA54Q Temporarily disable machines on any exception, not just connection failures
• [9] G7KWXSFM Distinguish build step states

Change contents

• edit in src/hydra-queue-runner/build-remote.cc at line 98
  [3.509]→[3.78:78](∅→∅)
  −
• replacement in src/hydra-queue-runner/build-remote.cc at line 318
  [3.2237]→[2.165:232](∅→∅)
  − worker_proto::write(*localStore, to, {step->drvPath});
  [3.2237]

  [3.2309]
  + worker_proto::write(*localStore, to, StorePathSet{step->drvPath});
• edit in src/hydra-queue-runner/build-remote.cc at line 447
  [3.2288]→[3.90:90](∅→∅)
  −