Merge staging into closure-size

The most complex problems were from dealing with switches reverted in
the meantime (gcc5, gmp6, ncurses6).
It's likely that darwin is (still) broken nontrivially.

pkgs/os-specific/linux/systemd/default.nix

@@ -12,20 +12,20 @@ assert stdenv.isLinux;
 assert pythonSupport -> pythonPackages != null;
 
 stdenv.mkDerivation rec {
-  version = "226";
+  version = "227";
   name = "systemd-${version}";
 
   src = fetchFromGitHub {
     owner = "NixOS";
     repo = "systemd";
-    rev = "16d61e9657b643cc25ff0538688eb870ce2dd4a5";
-    sha256 = "07sc1x43j60d5jnps0d7bfka10fihnpgkdrfrh9iskgmc9qangjb";
+    rev = "7d94d27801d20278103d8c146633fe81e06697d6";
+    sha256 = "0cvzsrazqgbia3zajb0z4ik8myfil4bdy2c29qs6w93d6yvrjfkj";
   };
 
   patches = [ ./hwdb-location.diff ];
 
   /* gave up for now!
-  outputs = [ "out" "libudev" "doc" ]; # TODO: "dev"
+  outputs = [ "out" "libudev" "doc" ]; # maybe: "dev"
   # note: there are many references to ${systemd}/...
   outputDev = "out";
   propagatedOutputs = "libudev";
@@ -168,8 +168,6 @@ stdenv.mkDerivation rec {
 
       rm $out/lib/*.la
 
-      rm -rf $out/share/doc
-
       # "kernel-install" shouldn't be used on NixOS.
       find $out -name "*kernel-install*" -exec rm {} \;
     ''; # */