Replace property 'name' with 'id' in nuxeo-operation element

Replace the attribute name with id in <dom-module name="nuxeo-operation">
The id is the correct and required attribute to use in <dom-module> element declaration.
Besides the fact that name attribute seems to work (maybe due to legacy compatibility with the older <polymer-element> syntax) it causes some warnings in IDE's/Polymer plugins (ex: IntelliJ IDEA)