Fix having to create new elements on each edit

[zachberry]

Spoke with someone on the Edge dev team who gave me some options to get around having to create elements with a datestamp, like <n1-12345678>.

1. There is an unregisterComponent. When editing a node I should be able to unregister, then re-register. For some reason I missed this in the docs when working on this.
2. The various lifecycle methods (onAttrChanged, onRemove, etc) could call another method. That way I wouldn't need to unregister then re-register, instead the user would be updating a method that the native web component would call. However this would introduce a second function call.