DATAREST-1384 - Create security policy readme.

Author: mp911de

SECURITY.adoc

@@ -0,0 +1,9 @@
+# Security Policy
+
+## Supported Versions
+
+Please see the https://spring.io/projects/spring-data-rest[Spring Data REST] project page for supported versions.
+
+## Reporting a Vulnerability
+
+Please don't raise security vulnerabilities here. Head over to https://pivotal.io/security to learn how to disclose them responsibly.