Manually catch exceptions raised by the fetch() method when receiving responses without CORS header (only inside the LayersList component).
This was especially problematic when one specific layer.json file doesn't exist on the server, if the 404 response returned doesn't contain a CORS header, the fetch() method doesn't accept the response and raise an exception. See stackoverflow.
A warning is now displayed in the console instead of crashing the app.
Fixes #10
Manually catch exceptions raised by the fetch() method when receiving responses without CORS header (only inside the LayersList component).
This was especially problematic when one specific layer.json file doesn't exist on the server, if the 404 response returned doesn't contain a CORS header, the fetch() method doesn't accept the response and raise an exception. See stackoverflow.
A warning is now displayed in the console instead of crashing the app.