factors.keep argument changed to 'factor' (default FALSE), which if TRUE keeps factors (which otherwise may be converted to characters)

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roxygen

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update

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up

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up

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up

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up

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up

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cran prep

git-svn-id: svn://svn.r-forge.r-project.org/svnroot/lava@1286 edb9625f-4e0d-4859-8d74-9fd3b1da38cb
unit-test updated

git-svn-id: svn://svn.r-forge.r-project.org/svnroot/lava@1287 edb9625f-4e0d-4859-8d74-9fd3b1da38cb