Implement a list of clubs

[palkerecsenyi]

One part of the app will be responsible for displaying a really simple, easy-to-navigate list of clubs.

Users should be able to (tick off this list as you go):

• [x] Enter their year group and ensure this gets saved to their device permanently
• [x] See a list of clubs, grouped by subject area
  • It's up to you how much data is displayed for each club in the list
  • Try finding a balance between information and a neat, concise view
• [x] Tap on a club to open a club info page (making the page itself is part of #3)

Club data querying has already been implemented — just see the lib/screens/clubs.dart file for where to put your code.