Roxygenized documentation

[iagomosqueira]

Rd files have been converted to roxygen using https://github.com/yihui/Rd2roxygen and it is now placed in the R files, before each function. #22

Rd files with no matching function, maybe left behind after code changes, are placed in man/vmstools-package.R.

I suggest also adding the flag to DESCRIPTION that allows use of markdown in the roxygen text.

Rd files have not been changed, but a call to

library(devtools)
document(roclets='rd')

worked just fine. You should delete all Rd files and reconstructed them with roxygen.