Exported events using an identifier are not parsed

[soft-decay]

At this line, identifiers are added to this.identifiers if they are top level variable declarations.

But later in the code, there is a similar code block handling variable declarations that are also exported (inside an ExportNamedDeclaration node), which does not add identifiers to this.identifiers.

Because of that, this is parsed ok:

const SIMPLE_EVENT = 'plain-notify';
dispatch(SIMPLE_EVENT); // emits event 'plain-notify'

But this is not:

export const SIMPLE_EVENT = 'plain-notify';
dispatch(SIMPLE_EVENT); // emits event SIMPLE_EVENT

Edit: This will be fixed by #56 but I'm creating a separate issue to help track bug fixes.