Multilevel categories

[KHardisty]

This is already submitted a couple times. Would be best to continue thumbs up over there.

https://community.hubspot.com/t5/HubSpot-Ideas/Adding-more-sub-categories-to-the-side-bar-menu-in-the-knowledge/idc-p/568029#M103172

https://community.hubspot.com/t5/HubSpot-Ideas/Multilevel-categories/idi-p/389639