OO-1071: a group with max number of participant set on 0 is always full

src/main/java/org/olat/group/ui/main/BGTableItem.java

@@ -121,9 +121,12 @@ public class BGTableItem {
 	
 	public boolean isFull() {
 		Integer maxParticipants = businessGroup.getMaxParticipants();
-		if(maxParticipants == null || maxParticipants.intValue() <= 0) {
+		if(maxParticipants == null || maxParticipants.intValue() < 0) {
 			return false;
 		}
+		if(maxParticipants.intValue() == 0) {
+			return true;
+		}
 		if(maxParticipants.intValue() <= (getNumOfPendings() + getNumOfParticipants())) {
 			return true;
 		}