Add time travel for tests

## Expected Behavior

In rails there is an inbuilt time travel implementation, and other alternatives like time cop. This is really great for tests. Is there really an [alternative for elixir](https://stackoverflow.com/questions/32903786/time-travel-and-time-freezing-in-elixir)?
## Current Behavior

Dates are hard coded for tests hence these tests are soon failing for the wrong when we are past some of these days.

## Possible Solution

See [timex](https://github.com/bitwalker/timex) or [time machinex](https://github.com/shinyscorpion/time_machinex)