Support for secrets stored in to vault in base64 encoded format(eg Truststore and Keystore) to Kubernetes secrets

[adityagu0910]

Hey
Thanks for this tool.

We have our keystore and truststore stored in base64 encoded in vault(as this is vault limitation, we can not store a binary file without encoding it to base64) and when we fetch them into kubernetes secret, the value get encoded again so when we mount these kubernetes secret into pod , we get base64 encoded value. while we want it to be actual keystore.

is it possible to add a flag(like below valyetype) in definition of "VaultSecret" which can tell that value is already base64 encoded and not to encode it when creating kubernetes secret.

- secretKey: trust.jks 
  kvPath: secret
  path: path 
  field: truststore
  **_valuetype: base64encoded_**