R: Vignettes and other documentation

# Vignettes and other documentation

## Vignettes from package 'callme'

callme::calling-r-from-c |  | Calling R from C | HTML | source | R code
callme::checking-for-interrupts |  | Checking for Interrupts | HTML | source | R code
callme::data-frames |  | Creating a data.frame in C | HTML | source | R code
callme::external-pointers |  | External pointers to C objects | HTML | source | R code
callme::introduction |  | Introduction | HTML | source | R code
callme::sexp |  | SEXP objects | HTML | source | R code
callme::third-party-libraries |  | Accessing 3rd-Party Libraries | HTML | source | R code