Signals backend
- Added backend code for signals, pressing the new signal button will now add a signal in the database
- Saved signals will be displayed on the map
- Fixed the design for the online status, it will now display users as offline when they close the app
- Fixed a bug where the send message bar would flicker every message sent
- Now actively tracking the user's position every 30 seconds while on main page
- Added comments to GoogleMaps.vue and firebase.js