Add warnings to VaultResponseSupport.

Fixes gh-36.

spring-vault-core/src/main/java/org/springframework/vault/support/VaultResponse.java

@@ -28,6 +28,5 @@ import com.fasterxml.jackson.annotation.JsonIgnoreProperties;
  * @author Spencer Gibb
  * @author Mark Paluch
  */
-@JsonIgnoreProperties(ignoreUnknown = false)
 public class VaultResponse extends VaultResponseSupport<Map<String, Object>> {
 }

spring-vault-core/src/main/java/org/springframework/vault/support/VaultResponseSupport.java

@@ -16,6 +16,7 @@
 
 package org.springframework.vault.support;
 
+import java.util.List;
 import java.util.Map;
 
 import com.fasterxml.jackson.annotation.JsonIgnoreProperties;
@@ -51,6 +52,8 @@ public class VaultResponseSupport<T> {
 
 	private boolean renewable;
 
+	private List<String> warnings;
+
 	/**
 	 *
 	 * @return authentication payload.
@@ -178,4 +181,20 @@ public class VaultResponseSupport<T> {
 	public void setRequestId(String requestId) {
 		this.requestId = requestId;
 	}
+
+	/**
+	 *
+	 * @return the warnings.
+	 */
+	public List<String> getWarnings() {
+		return warnings;
+	}
+
+	/**
+	 *
+	 * @param warnings the warnings.
+	 */
+	public void setWarnings(List<String> warnings) {
+		this.warnings = warnings;
+	}
 }