Add basic NPC generation functionality

[m-drzewko]

• Relegate races creation and saving to the database
• create entities for NPC and NPC dto
• create NPC repository
• create a service that will handle NPC generation and saving to the database via repository
• create a utility class that will contain common methods

If anything else needs to be added, do that as well.

[m-drzewko]

• [x] Relegate races creation and saving to the database
• [x] create entities for NPC and NPC dto DTO will be expanded later
• [x] create NPC repository
• [x] create a service that will handle NPC generation and saving to the database via repository saving to repository will be done later
• [x] create a utility class that will contain common methods