R: Revert update to version 3.1.1

This reverts commit 6e803a684fff2db30f6e10e8dc5a830184a12b9e. The new version
fails its test suite [1]. The issue has been reported upstream [2].

[1] http://hydra.cryp.to/build/191457/nixlog/1/raw
[2] https://bugs.r-project.org/bugzilla/show_bug.cgi?id=15975
haskell-arbtt: update to version 0.8.1.4
haskell-Chart-cairo: update to version 1.3.1
haskell-Chart-diagrams: update to version 1.3.1
haskell-Chart-gtk: update to version 1.3.1
haskell-Chart: update to version 1.3.1
haskell-DAV: update to version 1.0.2
haskell-aeson-qq: update to version 0.7.3
haskell-attoparsec: update to version 0.12.1.1
haskell-base-prelude: update to version 0.1.4
haskell-blaze-builder: update to version 0.3.3.3
haskell-boundingboxes: update to version 0.2
haskell-case-insensitive: update to version 1.2.0.0
haskell-checkers: update to version 0.4.1
haskell-criterion: update to version 1.0.1.0
haskell-cuda: update to version 0.6.5.0
haskell-diagrams-cairo: update to version 1.2.0.2
haskell-diagrams-lib: update to version 1.2.0.3
haskell-diagrams-rasterific: update to version 0.1.0.2
haskell-djinn: update to version 2014.9.7