Enhancements in security and viewing。

I added 'debug' configuring item (and default to FALSE) to disable `keys` operation because this is very very slow and may block the redis server.
And more, I added custom pagination controlling (by `from` & `to` param) , even support `zRangeByScore` and datetime as zSet's score value (datetime would be converted to timestamp). This is supported by 'cursor' param (`cursor` could be any of these: `index`, `score`, `datetime`)
Even more,  If the value is a serialized string. I would automatically unserialize the value.