Add of filling property for data on PI Vision Trends

Currently it is possible to edit color of the line, thicknes and other properies. As well it is incorporated the possibility to select the order in which trends are shown on the widget.

My proposal is to incorporate the possibility to fill the area below the trend with a specific color. This improvment would use the same 'order of appereance' rule applied on the lines and would allow for a lot of applications, such as:

• The use of this tool to highlight event frames on a trends, in case the event is associated with a flag that goes 0 to 1 to record the event;

• Implementation of stacked charts, that would allow for example to mark regions of interest on the display other than the sum of the contributions of different inputs;

• Also it would allow to highlit alarms on trends of process variables.

My proposal comes from different client inputs that would benefit from this improvement.