WIP PCA in FluidVecs
WIP PCA and PCA scoring on FluidVecs
Renaming a few internal methods, no behavioral changes
WIP PCA scoring functions with ValueArray PCA only
Automatically flip row to NA in PCA score if input contains NA
Deal with NAs in PCA scoring
Introduce prefix versioning in URL:

 - /GLM.json - old GLM
 - /2/GLM.json - Fluid vector based GLM
Python REST api wrapper modified.
downloadCsv renamed to DownloadDataset respecting class name.
Comments.
Merge remote-tracking branch 'origin/master' into vers
Merge remote-tracking branch 'origin/master' into vers
R Client now using v2.0 API for all pages based on Request2.
Merge remote-tracking branch 'origin/master' into vers
Merge remote-tracking branch 'origin/master' into vers
Updated Job.cancel to handle case when job is missing.
add r unit test for histograms
Fixed ParseDataset to remove job when done.
Merge remote-tracking branch 'origin/master' into vers
glm2, gbm, gbmgrid benchmark scripts