Added apt-get install libvirt for travis

.travis.yml

@@ -3,6 +3,7 @@ python:
   - 2.6
   - 2.7
 install:
+  - apt-get install -y python-libvirt
   - pip install --use-mirrors pyqcy mocktest PyContracts nose
   - python setup.py install
 script: nosetests

setup.py

@@ -35,5 +35,5 @@ setup(
 
     packages=find_packages(),
     test_suite='tests',
-#tests_require=['pyqcy', 'mocktest', 'PyContracts'],
+    tests_require=['pyqcy', 'mocktest', 'PyContracts'],
 )