Merge branch 'master' into staging-next

There ver very many conflicts, basically all due to
name -> pname+version.  Fortunately, almost everything was auto-resolved
by kdiff3, and for now I just fixed up a couple evaluation problems,
as verified by the tarball job.  There might be some fallback to these
conflicts, but I believe it should be minimal.

Hydra nixpkgs: ?compare=1538299

pkgs/tools/backup/wal-e/default.nix

@@ -25,7 +25,7 @@ pythonPackages.buildPythonApplication rec {
   meta = {
     description = "A Postgres WAL-shipping disaster recovery and replication toolkit";
     homepage = https://github.com/wal-e/wal-e;
-    maintainers = [ stdenv.lib.maintainers.rickynils ];
+    maintainers = [];
     license = stdenv.lib.licenses.bsd3;
     platforms = stdenv.lib.platforms.linux;
   };