Countries and Flags

Added more data in country details.
The cards screen has a top search bar to move fast to the desired country.
Improved search on the country list page, now the search finds the countries based on name, local name, capital or even the flag emoji.
The test duration is reduced to 3 minutes from 5, sounds where added to have better feedback when a drop is correct or not. Also when the test is finished a summary dialog is shown.