csvstat: flag to specify how many frequent values to display

Created by: lazuly

Csvstat is really a very useful tool, but it still could be better : the "frequent values" feature is apparently fixedly limited to 5 values. It would be great if this "5" value was only the default value, and could be altered by a new parameter, say "-f ".

For example : "csvstat -f 20 -c 3,7 --freq myfile.csv" would return the 20 most frequent values of colums 3 and 7. Today it (seems) impossible to exceed the limit of 5 values.

Best regards, thanks for this great kit.