#359 Post-Python 3: Edit Award Category doesn't validate Category ID

[Ahasuerus]

The "Edit Award Category" submission creation process (edit/ submitawardcat.py) doesn't validate the submitted Category ID (award_cat_id) value. As long as it's numeric, it will be used to build an XML payload. The resulting submission will be marked as longer valid by the submission review code, but the submission creation process shouldn't be able to get that far if the submitted Category ID is invalid.