Week 1: ViewEvents, Week 2: Feed

This MR contains code for the ViewEvents page.

Closes #1 (closed), #2 (closed), #5 (closed)

Preview:

https://www.youtube.com/watch?v=1C4vgQcyCWU [Mobile]

https://www.youtube.com/watch?v=CVeuKJtQY4Y [Desktop]

Live:

https://crowdalert-dev.herokuapp.com/view/-L424H09AAaYFM8XEQ31

https://crowdalert-dev.herokuapp.com/

Edit: I had to update this MR according to Google Maps API v3. Furthermore, I had to join the Week 2 stuff as both of them are tightly coupled.