Clarify .prop modifier interacting with components (#966)

* Clarify .prop modifier interacting with components

* Move .prop text into bullets

* Remove whitespace

Author: davidhewitt

src/v2/api/index.md

@@ -1742,7 +1742,8 @@ All lifecycle hooks automatically have their `this` context bound to the instanc
 - **Argument:** `attrOrProp (optional)`
 
 - **Modifiers:**
-  - `.prop` - Bind as a DOM property instead of an attribute. ([what's the difference?](http://stackoverflow.com/questions/6003819/properties-and-attributes-in-html#answer-6004028))
+  - `.prop` - Bind as a DOM property instead of an attribute ([what's the difference?](http://stackoverflow.com/questions/6003819/properties-and-attributes-in-html#answer-6004028)). If the tag is a component then `.prop` will set the property on the component's `$el`.
+
   - `.camel` - (2.1.0+) transform the kebab-case attribute name into camelCase.
   - `.sync` - (2.3.0+) a syntax sugar that expands into a `v-on` handler for updating the bound value.