currently installing the R-pacakge will leave the repo in dirty state, since
`CmakeLists.txt` is already checked in. This fixes the `cleanup`
script to not delete this file.
* fix cran check
* change required R version because of utils::globalVariables
* temporary commit, monotone not working
* fix test
* fix doc
* fix doc
* fix cran note and warning
* improve checks
* fix urls
* fix cran check
* add cleanup and bump up version number
* use clean in build
* Update Makefile