Addition to ' Filter folders in "man" ', as suggested by eibanez on May 14.

I was still experiencing the problem where <code>man/figures</code> was treated as a file when running <code>roxygenize()</code> or <code>document()</code> with Windows OS.

eibanez described the problem and suggested a solution (https://github.com/klutometis/roxygen/pull/248) which pretty much did worked for me, but I believe that it was missing two more places in the code (cf. https://github.com/tobiaskley/roxygen/commit/b5c8ec5b299153a32d68d2e1b749a5160bc9f86a).

Please forgive me that I did not know how to add my commit to the already existing pull request and for opening the new one. I hope that this will not be seen as unfriendly.