* Add per-version DB upgrade routine.
Update order stats index length as well.
* Use globally namespaced methods for DB updates.
* Avoid creating duplicate DB update actions.
* Look table class and installer
* New table + stats
* Working reports/initial population
* Remove test
* Refactor, remove depth
* Unused table
* Update todo
* Add docblocks and reorder get_insert_sql params for consistency
* Adjust css braces
* clear hook on deactivation
* PSR-4 category lookup
* linting CSS closing brace last char on line
* initialize category lookup table in unit tests
* missed linting fixes
* revert move of run_all_pending call
* use consistent reference for term_relationships in queries