openslide: Convert to new overlay system

pkgs/openslide/default.nix

@@ -0,0 +1,39 @@
+{ stdenv, autoreconfHook, pkgconfig, fetchFromGitHub
+, zlib, openjpeg, libtiff, cairo, libpng, gdk_pixbuf, libxml2, sqlite }:
+
+stdenv.mkDerivation rec {
+  version = "3.4.1";
+  name = "openslide-${version}";
+
+  src = fetchFromGitHub {
+    owner = "openslide";
+    repo = "openslide";
+    rev = "v${version}";
+    sha256 = "1g4hhjr4cbx754cwi9wl84k33bkg232w8ajic7aqhzm8x182hszp";
+  };
+
+  buildInputs = [
+    autoreconfHook
+    pkgconfig
+    zlib
+    openjpeg
+    libtiff
+    cairo
+    libpng
+    gdk_pixbuf
+    libxml2
+    sqlite
+  ];
+
+  # Not sure why this Windows test isn't failing under Linux
+  postPatch = ''
+    sed -i -e 's|AM_CONDITIONAL(\[WINDOWS_RESOURCES\], \[test x$RC != x\])|AM_CONDITIONAL([WINDOWS_RESOURCES], [false])|' configure.ac
+  '';
+
+  meta = with stdenv.lib; {
+    homepage = http://openslide.org;
+    description = "A C library that provides a simple interface to read whole-slide images.";
+    platforms = platforms.all;
+    license = licenses.lgpl2;
+  };
+}