Please add license and improve DSL

[452]

Please add license and improve DSL

this code have some extra movements

System.out.println(vaultResponse.getData().get("access_key"));
System.out.println(vaultResponse.getData().get("secret_key"));

can you make your code more beauty and shortly, something like this:

System.out.println(vaultResponse.get("access_key"));
System.out.println(vaultResponse.get("secret_key"));

vaultResponse.getCredential("secret_key")
vault.getCredential("secret_key")
credentials.getCredential("secret_key")
credentials.get("secret_key")

also, a credential can be some file like ssh .pem key, or plain .properties / return String base64

we need thinking about elastic Java DSL architecture