Spring Cloud Config Add support for renewing client side vault token

See prior art https://github.com/pivotal-cf/spring-cloud-services-connector/blob/master/spring-cloud-services-spring-connector/src/main/java/io/pivotal/spring/cloud/service/config/VaultTokenRenewalAutoConfiguration.java

Comment From: marbon87

Hi @spencergibb, are there any plans to implement this?

Comment From: spencergibb

Yes, but it is not scheduled.