TSGraph - step graph for dates needs to extend the x-axis max by one onterval #255
Description
The step graph for dates needs to extend the x-axis maximum by one interval. This is because for a date, the data value at the date starts at the date and extends to the next date interval. The current code works for line and other graphs that connect to the last date. However, step forward graphs truncate one interval of data and that interval may be of the most interest since it is the most recent.