package-level helpfile

[goldingn]

Something I always look for when getting started with a new package is a package-level helpfile, so I can do ?sdmbench and see some general information about the package, how to get started, and see a roadmap to the available functions.

sdmbench doesn't have one of these yet, but it would be great if it did. You can create one of these with roxygen by documenting a NULL in a script in the R/ folder, like spocc does here.

[goldingn]

(note the @docType package line here)

[boyanangelov]

Great idea, I just added this. I think the only reason I didn't think about adding it is that it was not mentioned in H. Wickham's "R Packages" book, which was otherwise really helpful!