Added rule to readme.

README.md

@@ -93,6 +93,37 @@ function test(): { foo: ReadonlyArray<number>; } {
 "no-return-readonly-array": [true, "include-type-arguments", "deep"]
 ```
 
+### ternary-format
+
+[![has-fixer-badge]][has-fixer-link]
+
+This rule ensure ternary operators are formated a certain way.
+
+*Example:*
+
+```ts
+// TODO: Add ternary-format rule example to ReadMe.
+```
+
+#### Options
+
+##### `allow-single-line`
+
+If set, single line ternary operators will be allowed.
+
+*Example:*
+
+```ts
+// Allow this.
+const foo = condition ? getX() : getY();
+```
+
+#### Default config
+
+```json
+"no-return-readonly-array": [true, "allow-single-line"]
+```
+
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