Editing, corrections, and filling out the wiki and knowledge base

Added the second creature upgrade to all factions, orcs, and neutrals. Noticed that flying creatures' cards lack the "Flying" ability (as a link), and all caster creatures (liches, mages, priests, druids, etc.) lack "Caster". Also, all second upgrades lack creature descriptions.

Added heroes to orcs and all factions where tables were used instead of heroes. Many scenario heroes are missing, or I couldn't find them.