[travis] fixup changing dirs

.travis.yml

@@ -39,7 +39,7 @@ before_install:
   - if [ "$CXX" = "clang++" ]; then export CXX="clang++-3.7" CC="clang-3.7"; fi
   - cd $HOME
   - test -d src || git clone --branch=travis http://users.dune-project.org/repositories/projects/dune-stuff-demos.git src
-  - cd src
+  - cd $HOME/src
   - git submodule update --init --recursive
   - cp config.opts/travis $HOME/travis.opts && export DCONTROL_ARG="--opts=--builddir=${DUNE_BUILD_DIR} ${HOME}/travis.opts"
   - echo removing modules ${MODULES_TO_DELETE}
@@ -47,8 +47,9 @@ before_install:
   - rm -rf ${MODULES_TO_DELETE} dune-stuff
   - mkdir -p ${DUNE_BUILD_DIR}/eigen/build
     wget -qO- http://bitbucket.org/eigen/eigen/get/3.2.4.tar.gz | tar xvz -C ${DUNE_BUILD_DIR}/eigen --strip-components=1
-    cd ${DUNE_BUILD_DIR}/eigen/build && cmake .. -DCMAKE_INSTALL_PREFIX=${INSTALL_DIR} && make install ; cd -
+    cd ${DUNE_BUILD_DIR}/eigen/build && cmake .. -DCMAKE_INSTALL_PREFIX=${INSTALL_DIR} && make install
   # workarounds for dune-testtools issue
+  - cd $HOME/src
   - ./dune-common/bin/dunecontrol ${DCONTROL_ARG} --module=dune-python configure
   - ${DUNE_BUILD_DIR}/dune-python/python2-env/bin/pip install -U pip
   - ${DUNE_BUILD_DIR}/dune-python/python3-env/bin/pip install -U pip