Update unsplash.flavour to fulfill unsplashs updates

flavours/unsplash.flavour/install.sh

@@ -5,7 +5,7 @@ echo "~> Grabbing a random image from unsplash.com..."
 mkdir -p /mnt/etc/wallpapers/
 
 for tag in {forest,ocean,sky}; do
-    wget https://unsplash.com/photos/$(curl https://unsplash.com/search/photos/$tag | grep -oE "photo=([a-zA-Z0-9_\\-]*)" | shuf -n 1 | sed -e "s/photo=//g")/download -O /mnt/etc/wallpapers/$tag-$(uuidgen).jpg
+    wget $(curl https://unsplash.com/search/photos/$tag | grep -oE 'content="http://images.unsplash.com/photo-([a-zA-Z0-9_\\-]*)' | sed -e 's/content="//g' | shuf -n 1) -O /mnt/etc/wallpapers/$tag-$(uuidgen).jpg
 done
 
 amf_return=0