[DOCS][no-unused-vars] improve documentation (typescript-eslint#172)

Author: bradzacher

Diff for: packages/eslint-plugin-typescript/docs/rules/no-unused-vars.md

@@ -1,9 +1,21 @@
 # Prevent TypeScript-specific constructs from being erroneously flagged as unused (no-unused-vars)
 
-This rule only has an effect when the `no-unused-vars` core rule is enabled.
-
 It ensures that TypeScript-specific constructs, such as implemented interfaces, are not erroneously flagged as unused.
 
+## Configuration
+
+***This rule only has an effect when the `no-unused-vars` core rule is enabled.***
+
+See [the core ESLint docs](https://eslint.org/docs/rules/no-unused-vars) for how to configure the base `no-unused-vars` rule.
+
+```JSON
+{
+    "rules": {
+        "no-unused-vars": "error",
+        "typescript/no-unused-vars": "error",
+    }
+}
+```
 ## Rule Details
 
 The following patterns are considered warnings: