treewide: use unstable-date instead of hash as version

pkgs/applications/networking/flent/http-getter.nix

@@ -2,8 +2,8 @@
 , curl, pkgconfig }:
 
 stdenv.mkDerivation rec {
-  name = "http-getter";
-  version = "20180606";
+  pname = "http-getter";
+  version = "unstable-2018-06-06";
 
   src = fetchFromGitHub {
     owner = "tohojo";

pkgs/applications/office/bookworm/default.nix

@@ -3,9 +3,7 @@
 
 stdenv.mkDerivation rec {
   pname = "bookworm";
-  version = "4f7b118281667d22f1b3205edf0b775341fa49cb";
-
-  name = "${pname}-2018-10-21";
+  version = "unstable-2018-10-21";
 
   src = fetchFromGitHub {
     owner = "babluboy";

pkgs/development/beam-modules/hex-registry-snapshot.nix

@@ -1,9 +1,9 @@
 {stdenv, writeText, fetchFromGitHub }:
 
 stdenv.mkDerivation rec {
-    name = "hex-registry";
+    pname = "hex-registry";
     rev = "11d7a24e9f53f52490ce255a6248e71128e73aa1";
-    version = "20180712.${rev}";
+    version = "unstable-2018-07-12";
 
     src = fetchFromGitHub {
         inherit rev;

pkgs/development/libraries/gsignond/default.nix

@@ -6,16 +6,15 @@
 let
 unwrapped = stdenv.mkDerivation rec {
   pname = "gsignond";
-  version = "39022c86ddb5062a10fb0503ad9d81a8e532d527";
+  version = "unstable-2018-10-04";
 
-  name = "${pname}-2018-10-04";
 
   outputs = [ "out" "dev" "devdoc" ];
 
   src = fetchFromGitLab {
     owner = "accounts-sso";
     repo = pname;
-    rev = version;
+    rev = "39022c86ddb5062a10fb0503ad9d81a8e532d527";
     sha256 = "1gw8vbj3j6wxqy759z97arm8lnqhmraw9s2frv3ar6crnfhlidff";
   };
 

pkgs/development/libraries/libsignon-glib/default.nix

@@ -2,15 +2,13 @@
 
 stdenv.mkDerivation rec {
   pname = "libsignon-glib";
-  version = "3639a2e90447e4640a03a44972560afe8f61aa48";
-
-  name = "${pname}-2018-10-24";
+  version = "unstable-2018-10-24";
 
   outputs = [ "out" "dev" "devdoc" "py" ];
 
   src = fetchgit {
     url = "https://gitlab.com/accounts-sso/${pname}";
-    rev = version;
+    rev = "3639a2e90447e4640a03a44972560afe8f61aa48";
     fetchSubmodules = true;
     sha256 = "1cq19zbsx4c57dc5gp3shp8lzcr1hw2ynylpn1nkvfyyrx80m60w";
   };