0030483: Visualization, Path Tracing - make Tile Size configurable

0030483: Visualization, Path Tracing - make Tile Size configurable

OpenGl_TileSampler has been refactored to better describe its logic:
- Offset image now defines tile index instead of offset to tile origin.
- Added 2D array defining the number of times to sample tile for straight-forward debugging.

Graphic3d_RenderingParams has been extended with property
RayTracingTileSize for testing various tile configurations.
Default behavior is the following:
- Target number of tiles (e.g. upper limit per frame): 256
- Tile size: 32x32.

OpenGl_View::runPathtrace() has been split into two methods per rendering stage.
OpenGl_Texture::Init() now returns FALSE immediately on 0 input dimensions.

Added Image_PixMapTypedData template class allowing to work with image data of known pixel format.