Is there a document describing exactly what was addad to the different versions of the opengl?
has a link that descibes in short what was added. For 1.3, I havent seen such a short document.
Click on “OpenGL Specification & Manual Pages” for long versions. Those are specs, they talk about everything in each version.
As for the extensions, there are specs at the registry.
All the links are on that same page.