fix removing entire twisted when uninstalling cyclone
fix removing entire twisted when uninstalling cyclone

'twisted' should not occur in the top_level.txt file as this
triggers a bug in pip that removes all of twisted when a package
with a twisted plugin is removed.

lextoumbourou/cyclone,fiorix/cyclone,lextoumbourou/cyclone,dpnova/cyclone,fiorix/cyclone,lextoumbourou/cyclone,fiorix/cyclone,dpnova/cyclone,dpnova/cyclone,dpnova/cyclone