Adding offset into rose_wind to be similar with openair::windRose

[zemega]

Hi.
I would like to add suggestion or a feature request. I have tried rose_wind, and I really want to utilise the offset option available in openair::windRose. After going through the codes, here are the modification I made.

rose_wind <- function(..., offset = NULL){
...
# Directly after 
# axis_extend <- axis_extend * 3 / 4
if (!is.null(offset)){
    axis_extend <- offset
}
...
}

That is all.