updated installation instructions

diff --git a/README.md b/README.md
index 27262d17bdbfe617545a694a3a793aaebeadea73..f04a7379f97e2141ac2a07b39f32eda3a407854b 100644 (file)
--- a/README.md
+++ b/README.md
@@ -13,6 +13,9 @@ Unless previously installed you'll need the following packages:
 - [Cairo](http://cairographics.org/)
 
 Please use their sites to get detailed installation instructions.
+You also need `UglifyJS` installed globally:
+
+    $ npm install uglify-js -g
 
 ### Install binb