Enable running rkt tests in travis

- Introduces a travis target in Makefile to update docker and
  install rkt

.travis.yml

@@ -21,7 +21,7 @@ branches:
     - master
 
 install:
-  - make prepare_docker
+  - make travis
   - make bootstrap
 
 script:

GNUmakefile

@@ -72,13 +72,8 @@ bootstrap:
     go get $$tool; \
 	done
 
-prepare_docker:
-	sudo stop docker
-	sudo rm -rf /var/lib/docker
-	sudo rm -f `which docker`
-	sudo apt-key adv --keyserver hkp://p80.pool.sks-keyservers.net:80 --recv-keys 58118E89F3A912897C070ADBF76221572C52609D
-	echo "deb https://apt.dockerproject.org/repo ubuntu-trusty main" | sudo tee /etc/apt/sources.list.d/docker.list
-	sudo apt-get update
-	sudo apt-get install docker-engine=$(DOCKER_VERSION)-0~$(shell lsb_release -cs) -y --force-yes
+travis:
+	@sh -c "'$(PWD)/scripts/update_docker.sh'"
+	@sh -c "'$(PWD)/scripts/install_rkt.sh'"
 
 .PHONY: all bin cov integ test vet web web-push test-nodep

scripts/install_rkt.sh

@@ -0,0 +1,11 @@
+#!/bin/bash
+
+set -ex
+
+RKT_VERSION="v1.0.0"
+DEST_DIR="/usr/local/bin"
+
+wget https://github.com/coreos/rkt/releases/download/$RKT_VERSION/rkt-$RKT_VERSION.tar.gz
+tar xzvf rkt-$RKT_VERSION.tar.gz
+sudo cp rkt-$RKT_VERSION/rkt $DEST_DIR
+sudo cp rkt-$RKT_VERSION/*.aci $DEST_DIR

scripts/update_docker.sh

@@ -0,0 +1,7 @@
+sudo stop docker
+sudo rm -rf /var/lib/docker
+sudo rm -f `which docker`
+sudo apt-key adv --keyserver hkp://p80.pool.sks-keyservers.net:80 --recv-keys 58118E89F3A912897C070ADBF76221572C52609D
+echo "deb https://apt.dockerproject.org/repo ubuntu-trusty main" | sudo tee /etc/apt/sources.list.d/docker.list
+sudo apt-get update
+sudo apt-get install docker-engine=$(DOCKER_VERSION)-0~$(shell lsb_release -cs) -y --force-yes