Adds demo to travis

.travis.yml

@@ -2,4 +2,5 @@ language: bash
 services: docker
 script:
 - ./build-me.sh
+- docker run --rm -v `pwd`/ci/demo:/demo --entrypoint=/demo falsifiable/popper
 - cd popper/_check && ./build_images

docs/ci/demo

@@ -0,0 +1,10 @@
+#!/bin/bash
+set -ex
+mkdir /tmp/mypaper
+cd /tmp/mypaper
+git init
+popper init
+popper init mypipeline
+popper ci travis
+cd pipelines/mypipeline
+popper check

popper/Dockerfile

@@ -1,6 +1,10 @@
 FROM golang:1.9
+
 ADD . /go/src/github.com/systemslab/popper
+
 WORKDIR /go/src/github.com/systemslab/popper
-RUN go get ./
-RUN go build
+
+RUN go get ./ && \
+    go build
+
 ENTRYPOINT ["/go/bin/popper"]