IntelliJ-Idea support, better SBT project setup

[sebnozzi]

This adds support for IntelliJ idea.

As far as I could see, there was no support for IntelliJ. This adds the ability to create projects and import them.

It also adds the JUnit runner, needed in IntelliJ.

Additionally, it adds the ScalaTest library via SBT. Projects generated through SBT will be able to link to the dependency.

[sebnozzi]

Whenever Eclipse issues a NPE when launching a ScalaTest file, be sure to "Add Scala to Library to Build Path" under menu "Scala" in the project...

[sebnozzi]

Now I realize you it is on purpose that you include the IDE project files, so that the user does not need to install SBT.

In that case the only thing you need from this pull request is the commit 6b3038a ("FIX - support for IntelliJ, etc."). Once you generate the IntelliJ project files (via SBT, invoking "gen-idea"). You can commit those files (if they don't have references to your local ivy2 cache) into the codebase

[acanda]

I'd like to keep the Eclipse files so this code works out of the box with the Dojo Perparation Guide.

[sebnozzi]

If it also supports IntelliJ out-of-the-box I'm fine with it :-)

Long term, though, people should learn to use SBT! :-)