More fixes to assign_categories.
More fixes to assign_categories.


Former-commit-id: 90b281aaef1887d7a7ccb3520c7c6d96843ffc9a
eggpi/citationhunt,guilherme-pg/citationhunt,eggpi/citationhunt,eggpi/citationhunt,guilherme-pg/citationhunt,guilherme-pg/citationhunt,eggpi/citationhunt,guilherme-pg/citationhunt