"stamped" event is dispatched before elements are stamped

[tomalec]

It seems I implemented https://github.com/Juicy/imported-template/commit/f33a5df8988773a1ffb2588fc6e91b8a8bc7cfb4 incorrectly. It fires an event stamped once link is appended to the tree so far before content is actually stamped to the tree.

I believe it should behave as described at https://github.com/Juicy/imported-template/blob/master/README.md#events, so we should fire this event at https://github.com/Juicy/imported-template/blob/4d927ec0f241359ee445fce88c8e1080405dcb61/imported-template.html#L88

See how it's done in juicy-html - it stamps just after nodes are appended to the tree. https://github.com/Juicy/juicy-html/blob/master/juicy-html.html#L121-L124