RedisClient.prototype.end function bug fixed.

An uncaught exception will be raised when the retry timer tries to
reconnect and encounter an error, for all event listeners of the stream
were removed in line 826. It should set closing varable to be true.
Merge pull request #303 from mowaken/master

fixed RedisClient.prototype.end()
Merge remote-tracking branch 'upstream/master' into fix_js_parser_error_bubbling