Created TicketController
Created Model/AbstractTicket, Entity/AbstractTicket, Entity/Ticket
Created Model/AbstractCategory, Entity/AbstractCategory, Entity/Category
Created Model/AbstractStatus, Entity/AbstractStatus, Entity/Status
Created Model/AbstractPriority, Entity/AbstractPriority, Entity/Priority
Created Entity/TicketManager
Created Entity/CategoryManager
Created Entity/StatusManager
Created Entity/PriorityManager
Added DataFixtures