needs.json like files per page or even ID

[danwos]

In huge projects the needs.json can become quite big (> 5 MB) and downloading it for only some information about a single need is not perfect.

We should create some additional builders to structure the needs-data in a different way:

• [ ] needs_per_page: Creates for each page a json file with containing needs.
• [ ] needs_per_id: Creates a single json file per need-id, e.g. REQ_ABC123.json
• [ ] needs_lookup: A single needs_lookup.json file, which contains id and docname only. Used by the permalink feature.

The above data structure would allow the efficient work in use cases like:

• needs permalink
• needs-viewer: a JS-based viewer to load single needs
• need-preview: A HTML previewer for selected needs