Change in setProgress method logic.

If showPercentage is true, then the percent is automatically calculated and displayed, otherwise the absolute value is displayed.
Backward compatibility of setProgress method.
Update ADVPercentProgressBar demo.

Assess the new feature of ADVPercentProgressBar.
Change in setProgress method logic.

Check range of current progress and pin to its limits if required.
Refactoring showPercent property.
Docunebt ADVPercentProgressBar class in doxygen format.
Demo update.

Refactoring integralProgressBars.
Update copyright notices.