Resolve "room image improvements"

What does this mr do?

Stuff that needed to be changed is described in a checkbox in the issue desc: #568 (closed)

Screenshots

No room map present

Room map present

Does this MR meet the acceptance criteria?

• I have added a changelog entry to reflect the significant changes I made.
• Tests were created to test the feature.
• I have updated the documentation accordingly.
• I adhere to the style guide.

Closes #568 (closed)

src/main/java/nl/tudelft/queue/cache/RoomCacheManager.java

@@ -17,8 +17,7 @@
  */
 package nl.tudelft.queue.cache;
 
-import java.util.List;
-import java.util.Set;
+import java.util.*;
 import java.util.stream.Collectors;
 
 import org.springframework.beans.factory.annotation.Autowired;
@@ -37,10 +36,16 @@ public class RoomCacheManager extends CoreCacheManager<Long, RoomDetailsDTO> {
 	private RoomControllerApi api;
 
 	public List<RoomDetailsDTO> getAll() {
-		var rooms = api.getAllRoomsById(api.getAllRooms().collectList().block().stream()
+		List<RoomDetailsDTO> rooms = api.getAllRoomsById(api.getAllRooms().collectList().block().stream()
 				.map(RoomSummaryDTO::getId).collect(Collectors.toList())).collectList().block();
 		register(rooms);
 
+		rooms = new ArrayList<>(rooms);
+
+		rooms.sort(Comparator
+				.comparing((RoomDetailsDTO r) -> r.getBuilding().getName())
+				.thenComparing(RoomDetailsDTO::getName));
+
 		return rooms;
 	}