Fixes #177 : use Java 6 (JavaSE-1.6) in all project config files

Copied from #177:

I wanted to take a look at the newest Vrapper sources, but my Eclipse wouldn't compile them. It spits out an error on String.isEmpty().

Now it so happens that Vrapper was started when Java 1.5 was still a supported target, in the mean time it seems that everybody removed it from his computer and simply forced a 1.6 or 1.7 JDK in the 1.5 execution environment, hence confusing Eclipse.

I am willing to find/replace in the project files, but what is the stance of others? Should we shoot for 1.6 or 1.7 minimum level?


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Odd that the previous issue gets no merge button - I thought github also offered it when commits are referenced in an issue.