Please add License

[patrickrobbins]

I may need to pull this down to customize, but there is no license. Apachee or MIT?

[mgroves]

I submitted a PR for Apache 2. Can't believe this has been missed all this time. Hopefully Apache 2 is correct - tagging @jeffrymorris to make sure

[patrickrobbins]

Thanks, that seems correct based on the couchbase.extensions version of session provider.