Tear down requests.Session instance at close
Tear down requests.Session instance at close

This avoids log-spew on modern unittest implementations 
which report unclosed file handles at the end of a run.
toastdriven/pysolr,upayavira/pysolr,django-haystack/pysolr,upayavira/pysolr,django-haystack/pysolr,toastdriven/pysolr