More complex data

I have started using more complex data (sample data from OpenMRS) in my tuple merge and join tests... I might supplement that with RODS test data soon too.

I am also starting to consider the scalability and distributions of the grid when it starts to get Big. I think that OGSA-DAI will oversee most of the data pulls and merging, but only across about a hundred nodes which would then store their results in repositories. That way any polling algorithms will only have to pull from about a hundred "super" nodes instead of tens of thousands of regular nodes. The same would go for resource discovery.