fixed design - connection should stay open on an exception

Author: DvirDukhan

src/main/java/com/redislabs/redisgraph/impl/api/ContextedRedisGraph.java

@@ -53,17 +53,11 @@ protected ResultSet sendQuery(String graphId, String preparedQuery) {
             return new ResultSetImpl(rawResponse, this, caches.getGraphCache(graphId));
         }
         catch (JRedisGraphRunTimeError rt) {
-            conn.close();
             throw rt;
         }
         catch (JedisDataException j) {
-            conn.close();
             throw new JRedisGraphCompileTimeError(j);
         }
-        catch (Exception e) {
-            conn.close();
-            throw e;
-        }
     }
 
     /**