Run the documentation generator

Follow this procedure to produce the source documentation.

1. Go to the top directory of your sources.
2. Create a file named overview.4gl, with a #+ comment describing your project.
3. Go to the subdirectories and create files named package-info.4gl with a #+ comment describing the package.
4. Edit the .4gl modules to add #+ comments to functions that must be documented.
5. Go back to the top directory of your sources.
6. Run fglcomp --build-doc overview.4gl
   Use the -W apidoc compiler option to get warnings for invalid comment tags. For example, when a @param tag is missing for a function parameter.
7. To test the result, load the generated index.html file in your preferred browser.