Network services were upgraded

[erikbasargin]

Description

Added just simpler version of the network layer. From this moment services are responsible only for making requests and general configurations. For example, StackexchangeNetworkService gives us availability to make get requests to the stack exchange server with common query params.

How has this been tested?

1. Open the app
2. Check that everything is fine

Checklist

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes

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Closes #89