I am planning on getting a rasberry pi b+ for a specific use case and I have many questions(mostly about kits)Do I need the kit versions?Do they have things I need to use the rasberry pi?(Other than the case)Can I just buy only a rasberry pi?(of course ill need things like an HDMI cable to use it on a monitor but do these kits have necessary things or can I just use a rasberry pi by itself?)