Improve documentation of module types

I noticed that the docs here https://github.com/INCATools/ontology-development-kit/blob/master/docs/project-schema.md don't reflect all the options in the Makefile template here https://github.com/INCATools/ontology-development-kit/blob/master/template/src/ontology/Makefile.jinja2#L418, or explain what the options mean. Maybe this is documented somewhere else...

Compare docs/project-schema.md with the module-type options around line 418 of template/src/ontology/Makefile.jinja2. First identify every option in the Makefile template and check whether another documentation location already explains them. Done means project-schema.md, or the clearly referenced documentation, lists the available options and explains their meanings.

Written by the indexing model from the issue text.