XML display

[mosheduminer]

Currently, the /databases route is only capable of displaying JSON. We need to add complete XML functionality.

[mosheduminer]

The current implementation for the JSON resource view:

• A data structure allowing access to any XML metadata-node by path. The reason for this is to allow for a flat DOM structure, as a nested DOM would make a virtual list implementation very complicated.
• A virtual list implementation (as the DOM would get start getting heavy, and slow down). This virtual list renders the wrapper component.
• A wrapper that accepts a path, and retrieves the appropriate nodes, and determines which svelte components to render for each node. It also determines whether diffs need to be rendered for the given path, and renders the appropriate components.

I would imagine that an XML view would follow a similar pattern.

The resource view also supports lazy-loading, depth-wise, and breadth-wise. This should be implemented for XML as well.