Merge pull request discourse#1398 from ZogStriP/patch-1

Add imagemagick dependency

Author: eviltrout

docs/INSTALL-ubuntu.md

@@ -48,7 +48,7 @@ If you have a mail server responsible for handling the egress of email from your
 Install necessary packages:
 
     # Run these commands as your normal login (e.g. "michael")
-    sudo apt-get -y install build-essential libssl-dev libyaml-dev git libtool libxslt-dev libxml2-dev libpq-dev gawk curl pngcrush python-software-properties
+    sudo apt-get -y install build-essential libssl-dev libyaml-dev git libtool libxslt-dev libxml2-dev libpq-dev gawk curl pngcrush imagemagick python-software-properties
 
     # If you're on Ubuntu >= 12.10, change:
     # python-software-properties to software-properties-common