Integrate realm into the Reminders App

[StanevPrime]

As a developer I want the realm package to be integrated as a new flavour into the Reminders app so that I can see how it compares to the already implemented Firebase solution.

ACs

• Two flavours should be added to the Reminders app (local storage and cloud storage)
  • Realm Local Storage should be implemented with minimal changes to the cloud solution
  • Realm Atlas flexible sync storage to be integrated in to the Reminders app
    • https://www.mongodb.com/pricing the Shared should be used
    • The implementation should support real time updates in the cloud flavour
    • Check if an issue similar to this is presented in realm library
  • The Firebase Authentication should remain unchanged
  • Both flavours should use encryption
  • The newly added flavours should not amend the established Reminders App Architecture

[StanevPrime]

@kostadin-damyanov-prime, please review and adjust the ACs if needed