Add Poll and Response models and API

[Glavin001]

See previous issue #12.

• [x] Poll model and API
  • [x] Poll's stats
• [x] Response model and API
  • [x] Respond to Poll

[Glavin001]

Example Polls:

[
        {
            id: 1,
            date: date,
            question: "What is your favorite brand of lays chips",
            answers: [
                { name: "BBQ", responses: 12 },
                { name: "Sour Cream and Onion", responses: 12 },
                { name: "Plain", responses: 12 }
            ]
        },
        {
            id: 1,
            date: date,
            question: "What is your favorite brand of lays chips",
            answers: [
                { name: "BBQ", responses: 12 },
                { name: "Sour Cream and Onion", responses: 12 },
                { name: "Plain", responses: 12 }
            ]
        },
    ]

[Glavin001]