The editor saga was assuming that main.py always exists, which is not
the case for the first use of the app. This fixes the issue by checking
to see if the file exists before attempting to open it. This also
revealed a bug in fileStorage where the list of files was not populated
during initialization.
This removes use of the pseudo-internal toString() function and also
removes extraneous uses of ReturnType<>. Also, a new when() method
is added to simplify additional uses.
The pattern we were using for actions required actions to be defined in
three places, an enum member containing the type string, an type
definition and a function. This combines all three of these into one by
using a helper function based on the ideas from [1].
[1]: https://phryneas.de/redux-typescript-no-discriminating-union
This replaces the localStorage file storage with a new backend that uses
localForage (indexeddb) for storing the file contents. This will also
allow storing multiple files.
David Lechner