
plot week axis
week_axis.Rd`week_axis()` adds labels to x axis on plots
Arguments
- y_height
- numeric, value of plot y height. Default to `graphics::par("usr")[4]`. 
- y_min
- numeric, value of minimum y height. Default to `graphics::par("usr")[3]`. 
- weeks
- numeric, number of weeks to plot. 
- factor
- numeric, factor used to determine position of calendar text. 
- language
- character, one of c("FR", "EN")