Update vault sdk to get CredentialsConfig.Logger (hashicorp#24)

Add a logger to awskms (hashicorp#22)

Allows for logging during awskms setup, to aid in debugging.

Add lookup function to multiwrapper and simplify

Add Yandex.Cloud KMS wrapper (hashicorp#20)

* Add Yandex.Cloud KMS wrapper

* Fix Yandex.Cloud KMS wrapper related issues

testing: Add an envelope option to TestWrapper (hashicorp#18)

* testing: Add an envelope option to TestWrapper

* Update wrapper_testing.go

Move structs to protobuf format (hashicorp#17)

Rename proto file to avoid conflict

Update vault dep

Update README

Add structwrapping package, which can wrap structs automatically via …

…tags (hashicorp#9)