Added basic disclosure

SECURITY.md

@@ -0,0 +1,13 @@
+# Security Policy
+
+## Supported & Maintained Versions
+
+| Version | Supported          |
+| ------- | ------------------ |
+| 0.x.x   | :white_check_mark: |
+
+## Reporting a Vulnerability
+
+Individuals or organizations that are experiencing a product security issue are strongly encouraged to contact the [project maintainers](mailto:security@bitcoinschema.org).
+We welcome reports from independent researchers, industry organizations, vendors, customers, and other sources concerned with our project security.
+The minimal data needed for reporting a security issue is a description of the potential vulnerability.