Gets the forestplot legend grobs
prFpGetLegendGrobs(legend, txt_gp, title)
list
A "Legend" class that derives from a
list with all the different legends. The list also contains
attributes such as height, width, max_height,
max_width, line_height_and_spacing. The title of the
legend is saved inside attr("title")
Legend corresponding to the number of bars
Set the fonts etc for all text elements. See fpTxtGp
for details
The title of the plot if any