no issue
- adds abolsute->relative and relative->absolute transformer methods to card definitions
- allows for each card to tailor it's transformation to the specific needs of it's payload so that the `mobiledoc` field can be transformed successfully during API serialization/deserialization
no issue
We're creating tooling to convert HTML to Ghost flavoured mobiledoc, however we have cards that allow arbitrary content without a wrapper element which means that we're unable to do a 1:1 mapping of mobiledoc->html->mobiledoc. To work around this problem we now output HTML comments before/after the output of each card so that our converter can extract card content correctly when parsing HTML.
- added `createCard` method which wraps a card's `render()` method to add begin/end comments and updated all cards to use it
- only takes affect for newly added or re-saved posts/pages
