Define article's assets

[csarven]

In Save As, the user can choose to copy relative URLs of @src, link@ref, object@data.

The assumption there is that media, CSS, and JavaScript are of interest to copy over.

Are there other resources that can or should be copied? For example, Issue #92 decided that an article's inbox need not be copied (with the possibility to offer an option to reuse/set the value).

[csarven]

With the commits https://github.com/linkeddata/dokieli/commit/b8049fcb27229cf0c41fb5470924e13f7c7e7613 and https://github.com/linkeddata/dokieli/commit/ad8a95c686627ca9ab9660c6ba10e9c47147a6ce , it is possible to optionally set article's inbox and annotation service with resource browser.