Add security policy file

See https://help.github.com/en/articles/adding-a-security-policy-to-your-repository

Author: MikeMcQuaid

SECURITY.md

@@ -0,0 +1,14 @@
+# Security Policy
+
+## Supported Versions
+
+Homebrew is a rolling release package manager. This means:
+
+- only the latest release and latest commit on the `master` branch of Homebrew/brew are supported
+- only the latest commit on the `master` branch of Homebrew/homebrew-core (and all other Homebrew taps) are supported.
+
+## Reporting a Vulnerability
+
+See the ["Security" section of our README](https://github.com/Homebrew/brew/blob/master/README.md#security) for instructions on how to support a security vulnerability.
+
+We will respond to and fix reported, reproducible security vulnerabilities as soon as possible. A gentle reminder that we are a volunteer-run project so please cut us some slack here.