Refactor model data structure

[martinleopold]

It seems to be hard to deal with, due to deep nesting. E.g. a specific annotation is at: Project.timeline.tracks[i].annotations[j]. Could help with DB/persistence too.

Keywords: normalised, flat structure

See:

• How to cut the boilerplate when updating nested entities? reduxjs/redux#994 (comment)
• https://github.com/paularmstrong/normalizr
• Question: Normalizr usage with nested objects in React/Redux reduxjs/redux#1255 (comment)
• https://www.firebase.com/docs/web/guide/structuring-data.html

[martinleopold]

Also:

• Integrate video data into the model. Currently it’s separated and it’s hard to see whats going on, since there are different flows of data going on.

[dinony]

Fixed in v0.1.0