Clarifying single machine install works as well

doc/install/Production-Ubuntu.md

@@ -2,7 +2,8 @@
 
 ## Install Ubuntu Server (x64) 14.04 LTS
 1. Set up 3 machines with Ubuntu 14.04 with 2GB of RAM or more.  The servers will be used for the Load Balancer, Mattermost (this must be x64 to use pre-built binaries), and Database.
-1. Make sure the system is up to date with the most recent security patches.
+   - **Optional:** You can also use a single machine for all 3 components in this install guide, depending on the standards of your data center.
+2. Make sure the system is up to date with the most recent security patches.
   * ``` sudo apt-get update```
   * ``` sudo apt-get upgrade```