Add imagemagick to circle
diff --git a/circle.yml b/circle.yml
index 2dc561d..520fe19 100644
--- a/circle.yml
+++ b/circle.yml
@@ -35,6 +35,7 @@
   cache_directories:
     - ~/sauce-connect
   pre:
+    - sudo apt-get update; sudo apt-get install imagemagick
     - ? |-
         mkdir -p ~/sauce-connect
         cd ~/sauce-connect