Support protobuf serialization

[glav]

Hi all,
When caching large amounts of data, the serializer used plays an important role. Protobuf is currently faster than all .NET-provided serializer
Since the Enym memcache client already supports protobuf serializer through protobuf-net.Enyim NuGet package, it would be great to extend this support to the rest of the caching mechanisms provided by CacheAdapter.
I would definately like to be able to change the serializers in the config file (from Binary to Xml to Protobuf and so on).
Let me know your thoughts on this.
Thanks, Simo

[glav]

Issue raised by @savornicesei on 2014-01-31 on Bitbucket.