Kie server: add war assemblies and move integ. tests into own module

@etirelli @mrietveld please review the changes and let me know if there is anything I could fix/enhance.
The reason I had to add this is because the different versions of Jackson are behaving differently (by default). In Jackson 1.x, used in EAP 6.x and currently in the client, the JAXB annotations are ignored and the Jackson 2.x used in WildFly 8 obeys them, so by default the JSON output was different when coming from EAP 6.x (any other container) and WildFly8. 

The second option here is to somehow configure the Jackson 2.x to ignore the JAXB annotations.
However, that would lead to the state where the XML output and JSON output are a little different. For example in the XML the field would be called `release-id` and in JSON `releaseId`. Yes, this is very minor difference, but this I though it would be nice to have the outputs consistent.

If the client uses Jackson 2.x, then it should not need to configure anything. However, for Jackson 1.x the above configuration would be required. Or we could do it the other way around.

I am not much familiar with the JSON marshaling, so if it caused serious problems in past, then I agree we should reconsider the default approach.