Cure off-by-one error in IntAllocator

Author: Emile Joubert

projects/client/RabbitMQ.Client/src/util/IntAllocator.cs

@@ -155,7 +155,7 @@ public int Allocate()
         return unsorted[--unsortedCount];
       } else if (Base != null) {
         int result = Base.Start++;
-        if(Base.Start == Base.End) Base = Base.Next;
+        if(Base.Start > Base.End) Base = Base.Next;
         return result;
       } else {
         return -1;