Add "Meetup" Feature

[MatthewHightech]

1. Add a meetup button inside the group page
2. Have the app check if your location has changed every (x) seconds and update their current position in the data base if it's changed
3. OnClick of the "Meet button" return all the positions from each member of the group and find the central position.
4. Send a query to the Maps API from the center point, searching for the 3 closest locations that meet the filter requirements.
5. Draw a pin on each location, to display location data when clicked