[server] add logging

[danielblagy]

• [x] research which logger is best to use for the project
• [x] research how to go about logging and unit testing
• [ ] implement logger wrapper
• [ ] add logging to internal services & handlers
• [ ] fix unit tests

Logger wrapper must use fast console logging package, and have a filed describing the context.

[danielblagy]

• [x] do research on spans (command line output)