Improve Language Documentation

I have to admit I'm really suprised that #1287 was finally merged. Surprised in a very good way because I think it is a very convenient thing to have a complete language documentation directly next to the source code. I know that this pull request had probably some delay due to the reason that it isn't so nice to have actually duplicated information, but having the documentation also directly available and nicely to read in Github is a nice thing as I believe.

Nevertheless there is still a lot to improve on this front so I want to proceed with the following modifications:
  - I updated the language doc to the latest source
  - I made the line number generator configurable and deactivated it for this built, the reasoning behind is, that I think it is not efficient to re-generate it every time someone included a line in a file (due to the reason that the line number would shift with that)
  - I improved the generator which now shows the state during the generation phase