documentation is out-of-date or wrong

The documentation seems to be very out-of-date everywhere I look. Here are some examples:

The GitHub readme at [subscriptions-transport-ws](https://github.com/apollographql/subscriptions-transport-ws) makes reference to a functions `graphqlExpress()` and `graphiqlExpress()`. These functions don't seem to exist anymore, nor be the proper way to go. From what I can tell the new way to go about this is something like:

```
const app = express();
const apolloServer = new ApolloServer(...);
apolloServer.applyMiddleware({ app });
...
```

The docs at [graphql-subscriptions](https://www.apollographql.com/docs/graphql-subscriptions/setup.html) also makes references to `graphqlExpress()` and `graphiqlExpress()`. Further, these docs link to a [tutorial on Medium](https://blog.apollographql.com/tutorial-graphql-subscriptions-server-side-e51c32dc2951?_ga=2.182672226.533310908.1541058553-2072463569.1540029911) which also reference `graphqlExpress()` and `graphiqlExpress()`.

I feel like I'm feeling my way through the dark on this and not sure which docs to trust and they all seem consistently wrong and/or out-of-date.

Start by comparing the GitHub README, the graphql-subscriptions setup documentation, and the linked Medium tutorial against the current usage shown in the issue. Identify references to graphqlExpress() and graphiqlExpress(), then update the affected documentation and links so they describe the current ApolloServer and applyMiddleware approach.

Written by the indexing model from the issue text.