Without this change, generated Swagger spec for the upload operation
does not have `container` parameter even it's a variable on the path.
As a result, the sepc fails validations.
An optional `container` is added to the remote method. Conditional
check is added to ensure backward compatibility.
Stop sending constructing the error response directly inside the
storage component and send the error back to the application to handle
it.
As a result:
- `File.afterRemoteError` hook is trigered now
- App-provided error handling strategy is used to build error
responses, e.g. using the production mode of strong-error-handler
to hide sensitive information.
Filename is replaced when `getFilename` is set in the options, this commit sets a new property called `originalFilename` to keep the original filename (only works when you upload the file, after that you need to save it in a model).