Gradle

This adds the [Gradle](http://www.gradle.org/) build tool so that Storyteller can be run from other IDEs or the command line (`gradle run` will start up the server).

Instructions on how to Eclipse-ify this will be coming eventually. They'll be added as a piece of documentation to this pull request.

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So, what does this do?

Basically, everything is moved to `src/main/java` or `src/test/java` depending on what it is, which lets us use the built in java plugin for gradle. The java plugin gives us a bunch of default tasks which are fairly useful.

It also removes all the jar files from the repository (except for our http server, which will hopefully be removed from the repository soon / eventually), and uses Gradle to download the jars for us.

The eclipse plugin is also included in our gradle file, which lets us simply run `gradle eclipse`, and create an entire eclipse workspace (with everything we need). The only additional work that needs to be done once the project is imported is to convert it to a gradle project. From there, you can run gradle tasks, and configure your green button to use the run task. A full set of instructions will be added soon.