added plot.SpatialPredictions.R function

git-svn-id: svn://svn.r-forge.r-project.org/svnroot/plotkml@504 edb9625f-4e0d-4859-8d74-9fd3b1da38cb
replaced "Parsing" with "Writing"

git-svn-id: svn://svn.r-forge.r-project.org/svnroot/plotkml@505 edb9625f-4e0d-4859-8d74-9fd3b1da38cb