public PromptedTimeRangeFilter(Prompt rangePrompt)
Create a filter to return a specific range of members. Range can represent
periods to date for a selected time level. In the PTD case, ending
period is the most recent member in the cube at the selected level.
Opening period is the descendant at the same level whose level 1
ancestor is the same as the ending period's. So in this implementation,
periods to date are returned as a rangeExample:
If user selects Quarter and the most recent Quarter entered is
Q3 2004, opening period will be Q1 2004.
rangePrompt - a range prompt for selecting start and end date members