Fail tests fast

.travis.yml

@@ -104,7 +104,7 @@ script:
   - python -c 'import theano; print(theano.__version__)'
   - python -c 'import theano; print(theano.config.__str__(print_doc=False))'
   - python -c 'import theano; assert(theano.config.blas.ldflags != "")'
-  - pytest -r A --verbose --runslow --cov=theano/ --cov-append --no-cov-on-fail $PART
+  - pytest -x -r A --verbose --runslow --cov=theano/ --cov-append --no-cov-on-fail $PART || travis_terminate 1
 
 after_success:
   - coveralls