Revert "Rename polymer and cr_elements v0_8 to v1_0"

third_party/polymer/v1_0/components/iron-signals/README.md

-iron-signals
-============
-
-`iron-signals` provides basic publish-subscribe functionality.
-
-Note: avoid using `iron-signals` whenever you can use
-a controller (parent element) to mediate communication
-instead.
-
-To send a signal, fire a custom event of type `iron-signal`, with
-a detail object containing `name` and `data` fields.
-
-```javascript
-this.fire('iron-signal', {name: 'hello', data: null});
-```
-
-To receive a signal, listen for `iron-signal-<name>` event on a
-`iron-signals` element.
-
-```html
-<iron-signals on-iron-signal-hello="{{helloSignal}}">
-```
-
-You can fire a signal event from anywhere, and all
-`iron-signals` elements will receive the event, regardless
-of where they are in DOM.