Check dependencies availability before bootstrap
Refactor update visible_to to use policy scopes

This solves the problem with Postgres DeadLook that some times happen on specs.
Merge pull request #297 from neighborly/jl-fix-deadlook

Refactor update visible_to to use policy scopes
Merge pull request #301 from neighborly/im-check-dependencies

Check dependencies availability before bootstrap
Use dotenv to store data of Configuration class
Remove fields using base_url and platform_fee from configurations