Make vtkProbeOpenGLVersion user friendly on windows.
- This executable lists out all opengl extensions and features in a message box. It wasn't very user friendly. The text was not scrollable and it was hard to see the complete list of capabilities even in a 4k screen.
- This commit refactors vtkWin32OutputWindow to show appropriate icons for the different message types. Error icon is displayed only for errors, warning icon for warnings and info icon for informative messages.
- It refactors the vtkProbeOpenGLVersion executable such that the long list of OpenGL capabilities is displayed in a scrollable window instead of a modal message box.
Edited by Jaswant Panchumarti (Kitware)