simpleHTTP raises exception on connection refused

When nothing listening on `localhost:81`, with following code:

```
(simpleHTTP (getRequest "http://localhost:81/")) >>= (\r -> case r of Left _ -> putStrLn "Error"; Right _ -> putStrLn "Alright!")
```

instead of printing `Error`, I get:

```
*** Exception: connect: does not exist (Connection refused)
```

To me, and as suggested by someone in `#haskell`, this seems like an unexpected behaviour. I'm expecting error condition to be passed in return value.

Thanks!

Start by reading the `simpleHTTP` and `getRequest` API paths shown in the issue, then inspect how connection-refused errors are handled and how `Either` results are returned. Reproduce the example with no service listening on localhost:81; done means the failure is returned as `Left` and the example prints `Error` rather than raising an exception. The issue names no files or tests.

Written by the indexing model from the issue text.