Field/questions order

Currently, the order of the children in the tree generated by xforms-engine is based on the order of the nodes in ``. It should be based on the controls in the ``.

This is a low priority issue, as it is extremely rare to see a mismatch between the order of `` and `` because pyxform orders them the same.

If we choose not to fix this, it would be nice to document this.

Start by locating the xforms-engine code that generates the tree and compare how children are ordered from nodes versus controls in . Reproduce a form where those orders differ, then verify that the generated tree follows ; if the project declines the behavior change, document the current ordering instead.

Written by the indexing model from the issue text.