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/applications/misc/onboard/default.nix

@@ -16,7 +16,7 @@
 , intltool
 , isocodes
 , libcanberra-gtk3
-, libudev
+, udev
 , libxkbcommon
 , pkgconfig
 , procps
@@ -79,7 +79,7 @@ in python3.pkgs.buildPythonApplication rec {
     hunspell
     isocodes
     libcanberra-gtk3
-    libudev
+    udev
     libxkbcommon
     wrapGAppsHook
     xorg.libXtst