fix(travis): increase ulimit

Now that performance tests are run, it appears we run into one
particular failure on travis, possibly indicating a bug in python 3.3.

Just bluntly increason the amount of handles might silence it... .

Related to #524

Author: Sebastian Thiel

.travis.yml

@@ -29,7 +29,7 @@ install:
   - cat git/test/fixtures/.gitconfig >> ~/.gitconfig
 script:
   # Make sure we limit open handles to see if we are leaking them
-  - ulimit -n 110
+  - ulimit -n 128
   - ulimit -n
   - nosetests -v --with-coverage
   - if [ "$TRAVIS_PYTHON_VERSION" == '3.4' ]; then flake8; fi