use Docker based travis config

 - mostly copied from https://github.com/KristofferC/PGFPlotsX.jl
 - using Debian Slim + SCIP requirements for Docker

Author: rschwarz

.travis.yml

@@ -4,15 +4,15 @@ os:
   - linux
 julia:
   - 0.6
-notifications:
-  email: false
-sudo: required
 dist: trusty
+sudo: required
+services:
+  - docker
 before_install:
-  - wget http://scip.zib.de/download/release/SCIPOptSuite-5.0.1-Linux.deb
-  - sudo dpkg -i SCIPOptSuite-5.0.1-Linux.deb
+  - echo "**** pulling Docker image"
+  - docker pull leethargo/debian4scip
+notifications:
+  email: false
 script:
-  - if [[ -a .git/shallow ]]; then git fetch --unshallow; fi
-  - julia -e 'Pkg.clone(pwd())'
-  - export SCIPOPTDIR="/usr"
-  - julia -e 'Pkg.build("SCIP"); Pkg.test("SCIP"; coverage=true)'
+  - echo "**** running Docker"
+  - docker run --env-file travis_docker_env.list -t -a STDOUT -a STDIN -a STDERR -v $PWD:/mnt leethargo/debian4scip /mnt/travis_docker_test_script.sh $TRAVIS_JULIA_VERSION

travis_docker_env.list

@@ -0,0 +1,10 @@
+# environment variables that are passed from Travis to Docker
+DOCUMENTER_KEY
+TRAVIS_BRANCH
+TRAVIS_PULL_REQUEST
+TRAVIS_REPO_SLUG
+TRAVIS_TAG
+TRAVIS_OS_NAME
+TRAVIS_JULIA_VERSION
+# comment this out to debug Documenter.jl
+# DOCUMENTER_DEBUG=true

travis_docker_test_script.sh

@@ -0,0 +1,20 @@
+#!/bin/bash
+
+# the first and only argument to the script is the version
+JULIAVER=$1
+JULIABIN=/test/julia-$JULIAVER/bin/julia
+PKGNAME="SCIP"
+
+## install the image (when necessary)
+/test/install-julia.sh $JULIAVER
+
+cd /mnt && if [[ -a .git/shallow ]]; then git fetch --unshallow; fi
+
+# run tests
+$JULIABIN -e "Pkg.clone(\"/mnt/\", \"$PKGNAME\"); Pkg.build(\"$PKGNAME\"); Pkg.test(\"$PKGNAME\"; coverage=true)"
+TEST_EXIT=$?                    # return with this
+
+# save coverage results back to host
+PKGDIR=`$JULIABIN -e "print(Pkg.dir(\"$PKGNAME\"))"`
+rsync -mav --include="*/" --include="*.cov" --exclude="*" $PKGDIR/ /mnt/
+exit $TEST_EXIT