Add implementation for Pudge

[recoilme]

https://github.com/recoilme/pudge

[philippgille]

Thanks for the feature request!

Pudge looks great and the performance is impressive. I see that similar to gokv Pudge accepts structs as well and you use gob to (un-)marshal it, so I'll have to see how I can make it work with the github.com/philippgille/gokv/encoding package, which allows the package user to choose if he wants to use Gob or JSON (or XML or others in the future), which I'd like to use for each implementation.

[recoilme]

Thank you! Feel free to ask me if you will have questions