Tab-completion doesn't word on imported symbol in REPL

In the REPL, none of the following would be completed with tab-completion:

```scala
scala> import java.util.HashMap
scala> val foo: HashM<tab> // No completion is offered, expected: "HashMap"
```

```scala
scala> import java.util.{HashMap => RenamedImport}
scala> val foo: Rena<tab> // No completion is offered, expected: "RenamedImport"
```