Add a chutney mode to travis.yml.

    # - env: HARDENING_OPTIONS=""

    ## We check asciidoc with distcheck, to make sure we remove doc products

    - env: DISTCHECK="yes" ASCIIDOC_OPTIONS="" SKIP_MAKE_CHECK="yes"

    # We also try running a hardened clang build with chutney on Linux.

    - env: CHUTNEY="yes" SKIP_MAKE_CHECK="yes" CHUTNEY_ALLOW_FAILURES="2"

      compiler: clang

      os: linux

  ## Uncomment to allow the build to report success (with non-required

  ## sub-builds continuing to run) if all required sub-builds have

  - if [[ "$COVERAGE_OPTIONS" != "" ]]; then pip install --user cpp-coveralls; fi

  ## If we're on OSX, and using asciidoc, configure asciidoc

  - if [[ "$ASCIIDOC_OPTIONS" == "" ]] && [[ "$TRAVIS_OS_NAME" == "osx" ]]; then export XML_CATALOG_FILES="/usr/local/etc/xml/catalog"; fi

  ##

  ## If we're running chutney, install it.

  - if [[ "$CHUTNEY" != "" ]]; then git clone --depth 1 https://github.com/torproject/chutney.git ; export CHUTNEY_PATH="$(pwd)/chutney"; fi

  ## Finally, list installed package versions

  - if [[ "$TRAVIS_OS_NAME" == "linux" ]]; then dpkg-query --show; fi

  - if [[ "$TRAVIS_OS_NAME" == "osx" ]]; then brew list --versions; fi

  ## We run `make check` because that's what https://jenkins.torproject.org does.

  - if [[ "$SKIP_MAKE_CHECK" == "" ]]; then make check; fi

  - if [[ "$DISTCHECK" != "" ]]; then make distcheck DISTCHECK_CONFIGURE_FLAGS="$CONFIGURE_FLAGS"; fi

  - if [[ "$CHUTNEY" != "" ]]; then make test-network-all; fi

  ## If this build was one that produced coverage, upload it.

  - if [[ "$COVERAGE_OPTIONS" != "" ]]; then coveralls -b . --exclude src/test --exclude src/trunnel --gcov-options '\-p' || echo "Coverage failed"; fi

  o Minor features (continuous integration):

    - Our Travis configuration now uses Chutney to run some network

      integration tests automatically. Closes ticket 29280.