Add support for Lidar intensity data

[alek-kam-robotec-ai]

This pr aims to add intensity support. It also:

• introduces wrapper classes for the native RGL Mesh, Entity and Texture pointers.
• Changes Mesh Library to Model Library which now also stores texture data.
• Adds intensity handling for both Mesh Components (based on their material) and terrain (based on globally set intensity texture (rgb or greyscale)) or a uniform intensity value.
• Mesh triangles are now aligned with the ones generated by the Terrain Gem (below - before and after the fix).
  
  

Known limitations:

• Textures obtained by processing Material Assets are not updated with every simulation reload. However, if a material component is modified so that it uses a different Material Asset (one that was not used before), this asset is then processed into a texture.
• Reflectance is calculated only from the albedo texture maps. This is a simplification. To achieve better realism, more material properties should be included in calculations.
• For now, only BC1 and BC4 formats are handled. Gamma corrected colors are not adjusted.
• Actor component is currently not supported.

[PawelLiberadzki]

Great updates! I responded to everything and put additional minor comments.

[msz-rai]

LGTM, good job! 👍

[alek-kam-robotec-ai]

I've rebased this branch.

[PawelLiberadzki]

Looks good!