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R.gitignore - Added .Rdata files
The "Writing R Extensions" manual lists RData as a valid file format for bundling data with an R package: http://cran.r-project.org/doc/manuals/r-release/R-exts.html#Data-in-packages
Looks like you're right. Would you like to open a Pull Request to remove this?
@arcresu sure, I've just opened #1245