This method returns a right-justified(right-aligned) string of given minimum width, using a specified character (space as default) as the fill character.
#length - It is the total length of the string that needs to be returned
after filling the specified characters on the left end(beginning) of the actual string.
#fillchar - (Optional) It is the specified character that needs to be filled
on the left end(beginning) of the actual string. By default it is space