Updating versions for 2.11.0-M3.

More hand-holding, please, from @adriaanm. /cc @JamesIry.

I tested that these URLs are okay with:

```
/code/scala-dist sbt
Detected sbt version 0.12.2
Starting sbt: invoke with -help for other options
Using /Users/jason/.sbt/0.12.2 as sbt dir, -sbt-dir to override.
[info] Loading project definition from /Users/jason/code/scala-dist/project
[info] Set current project to distribution (in build file:/Users/jason/code/scala-dist/)
> scala-dist-finish
Checking: akka-actors.jar
Checking: scala-actors-migration.jar
Checking: typesafe-config.jar
```

Incidentally, I was chatting to @jsuereth about this (somewhat untidy) neck of the woods, and it seems like a logical next step is to update `scala/scala` to publish the runner scripts as an extra artifact. Then, this project wouldn't need a checkout. I've lodged this as: [SI-7508](https://issues.scala-lang.org/browse/SI-7508).