Add Travis job for numpy-dev that is allowed to fail

Author: astrofrog

.continuous-integration/travis/setup_dependencies_common.sh

@@ -18,7 +18,12 @@ then
 fi
 
 # NUMPY
-conda install --yes numpy=$NUMPY_VERSION
+if [[ $NUMPY_VERSION == dev ]]
+then
+  pip install git+http://github.com/numpy/numpy.git  
+else
+  conda install --yes numpy=$NUMPY_VERSION
+fi
 
 # Now set up shortcut to conda install command to make sure the Python and Numpy
 # versions are always explicitly specified.

.travis.yml

@@ -19,8 +19,13 @@ env:
         - PYTHON_VERSION=3.4 SETUP_CMD='egg_info'
 
 matrix:
+
     include:
 
+        # Try developer version of Numpy
+        - os: linux
+          env: NUMPY_VERSION=dev SETUP_CMD='test'
+
         # Try MacOS X
         - os: osx
           env: PYTHON_VERSION=2.7 SETUP_CMD='test' OPTIONAL_DEPS=true
@@ -61,6 +66,9 @@ matrix:
         - os: linux
           env: PYTHON_VERSION=2.7 MAIN_CMD='pep8 astropy --count' SETUP_CMD=''
 
+    allow_failures:
+      - env: NUMPY_VERSION=dev SETUP_CMD='test'
+
 install:
     - source .continuous-integration/travis/setup_environment_$TRAVIS_OS_NAME.sh