Storage key should be encoded

[zeroid]

As part of the filenameFor (solid/kvplus-files/src/store.js line 149) function the key should be encoded to replace any invalid characters that cannot be part of a filename, in particular characters that might form part of a URI ( :, /, ?, #).

The reason for my request is that it appears OpenId authentication/authorization with solid/node-solid-server requires the JWT aud property/client_id to be a URI. This is enforced by way of the solid/oidc-auth-manager filterAudience function (solid/oidc-auth-manager/src/oidc-manager.js line 441).

Attempting to register a client with a URI for the client_id (e.g. via https://solid.community/register) fails with a 500 error which I believe to be the result of the server attempting to store the client information in a KVPFileStore using a URI key.

Disclaimer: I have not debugged this and my assumption is based solely on my reading of the code but this would seem a reasonable enhancement to make regardless.