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/tools/filesystems/convoy/default.nix

@@ -1,5 +1,5 @@
 # This file was generated by go2nix.
-{ stdenv, buildGoPackage, fetchFromGitHub, devicemapper }:
+{ stdenv, buildGoPackage, fetchFromGitHub, lvm2 }:
 
 buildGoPackage rec {
   name = "convoy-${version}";
@@ -14,7 +14,7 @@ buildGoPackage rec {
     sha256 = "0ihy0cfq7sa2wml904ajwr165hx2mas3jb1bqk3i0m4fg1lx1xw1";
   };
 
-  buildInputs = [devicemapper];
+  buildInputs = [lvm2];
 
   meta = with stdenv.lib; {
     homepage = https://github.com/rancher/convoy;