Added Dockerfile for building rudder

Dockerfile

@@ -0,0 +1,9 @@
+FROM ubuntu:12.04
+# Let's install go just like Docker (from source).
+RUN apt-get update -q
+RUN DEBIAN_FRONTEND=noninteractive apt-get install -qy build-essential curl git linux-libc-dev
+RUN curl -s https://storage.googleapis.com/golang/go1.3.1.src.tar.gz | tar -v -C /usr/local -xz
+RUN cd /usr/local/go/src && ./make.bash --no-clean 2>&1
+ENV PATH /usr/local/go/bin:$PATH
+ADD . /opt/rudder
+RUN cd /opt/rudder && ./build