Big refactoring.

- clubs, booking platforms and user are now defined in customization files -> there are less environment variables
- the responsibility of the session moved
- booking cancellation is available

booking.md

@@ -0,0 +1,44 @@
+MAIN:
+
+- Book court C of sport S at club X at time T for users U1,U2
+
+* X.has_ongoing_bookings(U1)
+* X.book(C, S, T, U1)
+
+- Cancel booking B at club X for user U1
+
+* X.cancel(B, U1)
+
+- Get tournaments of sport S at club X
+
+* X.get_tournaments(S)
+
+Club:
+
+- Book court C of sport S at time T for users U1,U2
+
+* new ClubUserSession
+
+- Cancel booking B for user U1
+- Has user U1 ongoing booking
+
+ClubConnector:
+
+- land
+- login user U
+- book court C of sport S at time T
+- has ongoing bookings
+- cancel booking B
+- get tournaments
+
+UserSession
+
++ user
++ session
++ connector
+
+- book
+
+* connector.land
+* connector.login
+* connector.land