Modified Notification API for icon and request pay load

Modified Notification API for icon and request pay load. Example: POST to api/v1/generate_notification

{
    "id": 2,
    "notification_title": "Title",
    "notification_body": "Body",
    "notification_icon": "hourglass",
    "notification_color": "none",
    "notification_type": "request",
    "associated_data":{
        "course": "SEG2105",
        "tutee": "Hannah"
    }

}

The payload will be used to generate the the following on the Front End:

RSalman / TutorBackend

Modified Notification API for icon and request pay load #51