git-svn-id: svn://svn.r-forge.r-project.org/svnroot/spatial-tools@133 edb9625f-4e0d-4859-8d74-9fd3b1da38cb
Allowed for arbitrary parameters to be passed to the user function (e.g. the function does not need to specify what is found in the args= parameter).

git-svn-id: svn://svn.r-forge.r-project.org/svnroot/spatial-tools@134 edb9625f-4e0d-4859-8d74-9fd3b1da38cb
git-svn-id: svn://svn.r-forge.r-project.org/svnroot/spatial-tools@135 edb9625f-4e0d-4859-8d74-9fd3b1da38cb