ViewerTest_EventManager now inherits AIS_ViewController.
Platform-dependent user input handling within ViewerTest has been revised
to process events in common way through AIS_ViewController.
The mouse navigation has been changed, so that left mouse clicked
without modifers now rotates View.
The rubber-band selection can be activated via Alt+LeftMouseButton.
Selection is now done on mouse unclick and keyboard short-cuts take effect on unclick.
Aspect_Window::SetTitle() - added new method configuring Window title.
Introduced new types Aspect_Touch, Aspect_VKey, Aspect_ScrollDelta
for processing window events in platform-independent way.
