PCA-doc-fix: Scree and cumulative variance plots (#291)
PCA-doc-fix: Scree and cumulative variance plots (#291)

Remove a paragraph in the PCA section that described how to retrieve
Scree and Variance plots. These are not available. This paragraph will
be added back in after PUBDEV-2788 is resolved.
mathemage/h2o-3,h2oai/h2o-3,mathemage/h2o-3,michalkurka/h2o-3,h2oai/h2o-3,h2oai/h2o-3,h2oai/h2o-3,spennihana/h2o-3,michalkurka/h2o-3,jangorecki/h2o-3,h2oai/h2o-3,mathemage/h2o-3,h2oai/h2o-dev,spennihana/h2o-3,spennihana/h2o-3,michalkurka/h2o-3,h2oai/h2o-dev,h2oai/h2o-3,michalkurka/h2o-3,mathemage/h2o-3,h2oai/h2o-3,h2oai/h2o-dev,michalkurka/h2o-3,spennihana/h2o-3,michalkurka/h2o-3,jangorecki/h2o-3,spennihana/h2o-3,mathemage/h2o-3,jangorecki/h2o-3,jangorecki/h2o-3,h2oai/h2o-dev,spennihana/h2o-3,h2oai/h2o-dev,michalkurka/h2o-3,h2oai/h2o-3,jangorecki/h2o-3,h2oai/h2o-dev,jangorecki/h2o-3,spennihana/h2o-3,mathemage/h2o-3,jangorecki/h2o-3,h2oai/h2o-dev,mathemage/h2o-3