Add url link in compressLevel documentation

Author: philippechataignon

man/fwrite.Rd

@@ -59,7 +59,7 @@ fwrite(x, file = "", append = FALSE, quote = "auto",
   \item{nThread}{The number of threads to use. Experiment to see what works best for your data on your hardware.}
   \item{showProgress}{ Display a progress meter on the console? Ignored when \code{file==""}. }
   \item{compress}{If \code{compress = "auto"} and if \code{file} ends in \code{.gz} then output format is gzipped csv else csv. If \code{compress = "none"}, output format is always csv. If \code{compress = "gzip"} then format is gzipped csv. Output to the console is never gzipped even if \code{compress = "gzip"}. By default, \code{compress = "auto"}.}
-  \item{compressLevel}{Level of compression between 1 (fastest method but less compression) and 9 (slowest compression method). The default compression level is 6 which is a good compromise.}
+  \item{compressLevel}{Level of compression between 1 and 9, 6 by default. See \url{https://linux.die.net/man/1/gzip} for details.}
   \item{yaml}{If \code{TRUE}, \code{fwrite} will output a CSVY file, that is, a CSV file with metadata stored as a YAML header, using \code{\link[yaml]{as.yaml}}. See \code{Details}. }
   \item{bom}{If \code{TRUE} a BOM (Byte Order Mark) sequence (EF BB BF) is added at the beginning of the file; format 'UTF-8 with BOM'.}
   \item{verbose}{Be chatty and report timings?}