Force pip and setuptool upgrade on travis

Author: pitbulk

.travis.yml

@@ -17,6 +17,7 @@ install:
   - sudo apt-get update -qq
   - sudo apt-get install -qq swig python-dev libxml2-dev libxmlsec1-dev
   - 'travis_retry pip install --force-reinstall --no-binary lxml lxml'
+  - 'travis retry pip install --upgrade pip setuptools'
   - 'travis_retry pip install .'
   - 'travis_retry pip install -e ".[test]"'