Use Ubuntu Trusty 14.04 as base image

Dockerfile

@@ -1,13 +1,13 @@
-FROM ubuntu:12.04
+FROM ubuntu:14.04
 MAINTAINER Jason Wilder jwilder@litl.com
 
 # Install Nginx.
+RUN echo "deb http://ppa.launchpad.net/nginx/stable/ubuntu trusty main" > /etc/apt/sources.list.d/nginx-stable-trusty.list
+RUN echo "deb-src http://ppa.launchpad.net/nginx/stable/ubuntu trusty main" >> /etc/apt/sources.list.d/nginx-stable-trusty.list
+RUN apt-key adv --keyserver keyserver.ubuntu.com --recv-keys C300EE8C
 RUN apt-get update
-RUN apt-get install -y python-software-properties wget
-RUN add-apt-repository -y ppa:nginx/stable
+RUN apt-get install -y  wget nginx
 
-RUN apt-get update
-RUN apt-get install -y nginx
 RUN echo "daemon off;" >> /etc/nginx/nginx.conf
 
 #fix for long server names