Export the remote adapter class

[kylef]

In the README we document the module as:

const { Fury } = require('fury');
const FuryRemoteAdapter = require('fury-adapter-remote');

const fury = new Fury();
fury.use(new FuryRemoteAdapter(options);

However, since we export an object with FuryRemoteAdapter as a property it errors out.

In this PR I have aligned implementation with the docs.