Add thumbnail-resizing script.

.gitignore

@@ -1 +1,2 @@
 /extern
+/thumbnails-small

scripts/resize-thumbnails.sh

@@ -0,0 +1,17 @@
+#!/bin/sh
+
+set -e
+
+cd "$(dirname "$0")"
+
+. ./settings
+
+cd ..
+
+rm -rf thumbnails-small
+mkdir thumbnails-small
+
+cd thumbnails
+for x in *; do
+    convert $x -resize x"$thumbnail_height" ../thumbnails-small/$x
+done

scripts/settings

@@ -0,0 +1 @@
+thumbnail_height=300