Add support for Creating, editing and viewing Product using Couchbase

[varsvat]

Fixes #FINCN-350

Adding support for following functionalities in Products' section:

• Create a new product
• Edit an existing product
• Product details Screen
• Add all the above features replacing the API interaction with the Couchbase interaction to extend offline support in the application
• Also replaced the existing MVP architecture with MVVM architecture recommended by Google itself

Please Add Screenshots If any UI changes.

Couchbase-server :

Sync-gateway :

https://user-images.githubusercontent.com/53621853/129941042-8b7a8381-386f-4f37-9dc1-870a41c808f2.mp4

https://user-images.githubusercontent.com/53621853/129941146-aca4972d-d52a-478b-9094-81ca3439c409.mp4

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