The GLAD function loader library is necessary for the renderer. While
it is possible to write one by hand, GLAD gets generated out of the GL
specification and works just fine.
The key for getting the path of the own module in the includes.txt is
no longer '{self}', but rather '{module}', as that is a little easier
to understand.
The include statements generated from the 'includes.txt' have'nt been
correct because of a prefixed string 'modules/' infront of the project
path. The local includes were also not working because the 'modules/'
path element was missing between the project path and the module name.
The build-script assumed that it was nested two levels deep from the
project's root directory, even if it is only nested one level deep;
that bug is now fixed.