Revert "[travis] disable dysfuncitonal osx builders"

This reverts commit 535dc63.

.travis.yml

@@ -4,15 +4,15 @@ before_install:
  - git fetch --depth=1000 --tags origin master
  - alias python=python${TRAVIS_PYTHON_VERSION}
  - if [[ "$TRAVIS_OS_NAME" == "linux" ]]; then sudo add-apt-repository -y ppa:pymor/stable ; fi
- - if [[ "$TRAVIS_OS_NAME" == "linux" ]]; sudo add-apt-repository -y ppa:fenics-packages/fenics ; fi
- - if [[ "$TRAVIS_OS_NAME" == "linux" ]]; sudo apt-get update -qq ; fi
- - if [[ "$TRAVIS_OS_NAME" == "linux" ]]; sudo apt-get install -y -qq python-docopt python-pytest python-opengl python-distribute ipython python-pyside python-pyvtk python-mpi4py ; fi
- - if [[ "$TRAVIS_OS_NAME" == "osx" ]]; brew install pyside open-mpi ; fi
+ - if [[ "$TRAVIS_OS_NAME" == "linux" ]]; then sudo add-apt-repository -y ppa:fenics-packages/fenics ; fi
+ - if [[ "$TRAVIS_OS_NAME" == "linux" ]]; then sudo apt-get update -qq ; fi
+ - if [[ "$TRAVIS_OS_NAME" == "linux" ]]; then sudo apt-get install -y -qq python-docopt python-pytest python-opengl python-distribute ipython python-pyside python-pyvtk python-mpi4py ; fi
+ - if [[ "$TRAVIS_OS_NAME" == "osx" ]]; then brew install pyside open-mpi ; fi
  - for pkg in ipyparallel pytest-cov python-coveralls ; do sudo -E pip install ${pkg} ; done
- - if [[ "$TRAVIS_OS_NAME" == "osx" ]]; sudo -E pip install docopt pytest pyopengl pyvtk mpi4py ; fi
+ - if [[ "$TRAVIS_OS_NAME" == "osx" ]]; then sudo -E pip install docopt pytest pyopengl pyvtk mpi4py ; fi
  # using aptitude here because it auto-fixes problems
- - if [[ "$TRAVIS_OS_NAME" == "linux" ]]; sudo aptitude install -y -q dolfin-dev python-dolfin ; fi
- - if [[ "$TRAVIS_OS_NAME" == "linux" ]]; python -c 'import  dolfin' || echo "import dolfin failed" ; fi
+ - if [[ "$TRAVIS_OS_NAME" == "linux" ]]; then sudo aptitude install -y -q dolfin-dev python-dolfin ; fi
+ - if [[ "$TRAVIS_OS_NAME" == "linux" ]]; then python -c 'import  dolfin' || echo "import dolfin failed" ; fi
 
 install:
  - python setup.py build_ext -i
@@ -84,4 +84,8 @@ addons:
 
 os:
   - linux
+  - osx
 
+matrix:
+  allow_failures:
+    - os: osx