make some correction to be sure that raster are red as continuous value and not as categorical ones (that will fix a lot of bugs)


git-svn-id: svn://svn.r-forge.r-project.org/svnroot/biomod@645 edb9625f-4e0d-4859-8d74-9fd3b1da38cb
primary dealing with non corectly evaluate models (to be improved)


git-svn-id: svn://svn.r-forge.r-project.org/svnroot/biomod@646 edb9625f-4e0d-4859-8d74-9fd3b1da38cb