Async loading for mission creation
As the API now handles asynchronous loading when creating missions, we should make the UI more tolerant to page reloads. For example, when source data is retrieved, redirect to mission page, explicitely showing that it's still loading pictures.
In order to let users know that something is happening, we can split loading time into steps :
- Retrieving features from data provider
- Waiting for image download
- Downloading images around features
Edited by Adrien Pavie