Added support Hashicorp-Vault

  * Added Vault plugin definitions.

Change-Id: Ib37e7cf01bb76dff8905a1d14fb0b3880ed03f5f
Related-Prod: PROD-29576
(cherry picked from commit 9c548ab1f4a467ec48378144c00fc91ed951d8b4)
diff --git a/README.rst b/README.rst
index 0557f46..3a1e1d0 100644
--- a/README.rst
+++ b/README.rst
@@ -302,6 +302,35 @@
             mkek_length: 32
             hmac_label: 'my_hmac_label'
 
+VAULT
+
+.. code block:: yaml
+
+    barbican:
+      server:
+        plugin:
+          vault:
+            schema: http
+            host: localhost
+            port: 8200
+            root_token_id: s.hpamtsbW5vcHFyc3R1dnd4eXo
+            approle_role_id: role_id
+            approle_secret_id: secret_id
+            kv_mountpoint: secret
+
+Vault supports secure connection. You able to define following fields for use security connection,
+also you should place file of certificate or define cert content in cacert field, in the last case
+`ssl_ca_crt_file` field required to define.
+
+.. code block:: yaml
+
+    barbican:
+      server:
+        plugin:
+          vault:
+            schema: https
+            ssl_ca_crt_file: '/etc/barbican/ssl/vault/CA.crt'
+            cacert: (certificate content)
 
 
 Software Only Crypto
@@ -352,6 +381,14 @@
             simple_cmc_profile: 'caOtherCert'
             ca_expiration_time: 1
             plugin_working_dir: '/etc/barbican/dogtag'
+          vault:
+            schema: http
+            host: localhost
+            port: 8200
+            root_token_id: s.hpamtsbW5vcHFyc3R1dnd4eXo
+            approle_role_id: role_id
+            approle_secret_id: secret_id
+            kv_mountpoint: secret
         store:
           software:
             crypto_plugin: simple_crypto