Add Firebase

[eduardoagr]

Since Azure doesn't offer an already setup back-end, firebase would be ago option to implement.

I recommend firebase realtime database, as is easier to set up, as opposed to cloud store.
One thing that we need to consider, is how will this page work? we will let the user select firebase as a plugin and redirect the user to the firebase console for the project creation or add a WebView, in order to maintain everything in the app

For my project I always use

https://github.com/step-up-labs/firebase-database-dotnet

HE ALSO HAVE ONE PACKAGE GOR AUTH