One Firebase Initialization in Main

[AnthonyOdum]

Describe the bug
We should have one Firebase initialization instead of multiple strewn throughout the code.

Expected behavior
If initialization fails, it can be handled before the request so the client doesn't lose data.

Additional context

• Firebase.init() should happen in Application.java
• projectID should be read in from a file instead of hard coded
• add getMapping("/") method back for pulse checking
• see if checking the firebase status is available to add