Close scanner when reached max_results.

When the suggest scanner has reached max_results, close the scanner.

This requires upstream fix for asynchbase for 0.96+:
OpenTSDB/asynchbase#91

src/uid/UniqueId.java

@@ -762,7 +762,12 @@ public Object call(final ArrayList<ArrayList<KeyValue>> rows) {
         }
         suggestions.add(name);
         if ((short) suggestions.size() >= max_results) {  // We have enough.
-          return suggestions;
+          return scanner.close().addCallback(new Callback<Object, Object>() {
+            @Override
+            public Object call(Object ignored) throws Exception {
+              return suggestions;
+            }
+          });
         }
         row.clear();  // free()
       }
@@ -1153,4 +1158,4 @@ public Map<String, Long> call(final ArrayList<KeyValue> row)
     get.qualifiers(kinds);
     return tsdb.getClient().get(get).addCallback(new GetCB());
   }
-}
+}