Specify whitespace rules for parentheses

Based on existing examples and <http://sideeffect.kr/popularconvention/#javascript>.

README.md

@@ -803,6 +803,30 @@
     });
     ```
 
+  - Place 1 space before the opening parenthesis in control statements (`if`, `while` etc.). Place no space before the argument list in function calls and declarations.
+
+    ```javascript
+    // bad
+    if(isJedi) {
+      fight ();
+    }
+
+    // good
+    if (isJedi) {
+      fight();
+    }
+
+    // bad
+    function fight () {
+      console.log ('Swooosh!');
+    }
+
+    // good
+    function fight() {
+      console.log('Swooosh!');
+    }
+    ```
+
   - Set off operators with spaces.
 
     ```javascript