Added nosetests.xml to the python unittest ignores.

nosetests.xml is created by the 'nose' test runner when you want xml output, for instance for integration with jenkins.

Python.gitignore

@@ -19,6 +19,7 @@ pip-log.txt
 # Unit test / coverage reports
 .coverage
 .tox
+nosetests.xml
 
 #Translations
 *.mo