treewide: remove aliases in nixpkgs

This makes the command ‘nix-env -qa -f. --arg config '{skipAliases =
true;}'’ work in Nixpkgs.

Misc...

- qtikz: use libsForQt5.callPackage

  This ensures we get the right poppler.

- rewrites:

  docbook5_xsl -> docbook_xsl_ns
  docbook_xml_xslt -> docbook_xsl

diffpdf: fixup

pkgs/development/tools/react-native-debugger/default.nix

@@ -1,5 +1,5 @@
 { stdenv, fetchurl, unzip, cairo, xorg, gdk_pixbuf, fontconfig, pango, gnome2, atk, gtk2, glib
-, freetype, dbus, nss, nspr, alsaLib, cups, expat, libudev, makeDesktopItem
+, freetype, dbus, nss, nspr, alsaLib, cups, expat, udev, makeDesktopItem
 }:
 
 let
@@ -19,7 +19,7 @@ let
     alsaLib
     cups
     expat
-    libudev
+    udev
 
     gnome2.GConf