PUBDEV-3677 - KMeans parameters
PUBDEV-3677 - KMeans parameters

Added missing parameters to the KMeans section in the user guide (under
Defining a Model).

h2oai/h2o-3,mathemage/h2o-3,jangorecki/h2o-3,h2oai/h2o-3,spennihana/h2o-3,michalkurka/h2o-3,h2oai/h2o-dev,h2oai/h2o-3,jangorecki/h2o-3,h2oai/h2o-dev,mathemage/h2o-3,michalkurka/h2o-3,jangorecki/h2o-3,michalkurka/h2o-3,michalkurka/h2o-3,h2oai/h2o-dev,michalkurka/h2o-3,h2oai/h2o-3,h2oai/h2o-3,h2oai/h2o-dev,michalkurka/h2o-3,jangorecki/h2o-3,mathemage/h2o-3,spennihana/h2o-3,mathemage/h2o-3,jangorecki/h2o-3,h2oai/h2o-dev,jangorecki/h2o-3,mathemage/h2o-3,spennihana/h2o-3,h2oai/h2o-dev,michalkurka/h2o-3,mathemage/h2o-3,mathemage/h2o-3,h2oai/h2o-3,spennihana/h2o-3,spennihana/h2o-3,h2oai/h2o-dev,h2oai/h2o-3,spennihana/h2o-3,spennihana/h2o-3,jangorecki/h2o-3,h2oai/h2o-3