components.md add Symbol to prop validation

Alex-Sokolov · chrisvfritz · commit 5539d8760a3e · 2017-05-10T13:38:16.000-04:00
diff --git a/src/v2/guide/components.md b/src/v2/guide/components.md
@@ -428,6 +428,7 @@ The `type` can be one of the following native constructors:
 - Function
 - Object
 - Array
+- Symbol
 
 In addition, `type` can also be a custom constructor function and the assertion will be made with an `instanceof` check.
 
