Major Description
Since we are building SparkR source package we are now seeing the call tree getting more convoluted and more parts are getting duplicated.
We should try to clean this up.
One issue is with the requirement to install SparkR before building SparkR source package (ie. R CMD build) because of the loading of SparkR via "library(SparkR)" in the vignettes. When we refactor that part in the vignettes we should be able to further decouple the scripts.
