Support for colons

[southwolf]

Colons : is a common practice for namespaced keys in Redis. It would be great if RedisView can display them correctly.

[cc20110101]

I thought about this feature at first, but it was not implemented for better performance.
Later, because of support key sorting, key pattern matching, I did not continue to consider this feature.
If the follow-up is really necessary, it can be implemented.