[Rd] missing `=` in man page for files2

[Ben Marwick]

Hi everyone,

In the example code at the bottom of this page, 
https://stat.ethz.ch/R-manual/R-devel/library/base/html/files2.html, 
there is a missing `=`. That page has:

f <- list.files(".", all.files = TRUE, full.names = TRUE, recursive  TRUE)

but it should be:

f <- list.files(".", all.files = TRUE, full.names = TRUE, recursive = TRUE)

It's also missing from built-in help pages, for example ?Sys.chmod

best,

Ben