The names of the links are rather tags than real names, and they sometimes vary
greatly in their spelling:
- GitHub: github, Github
- Source code: Repository, SCM, Project Source Code
- Documentation: docs, Documentation
It was standardized to terms such as 'Source code' and 'Documentation', as
translations already exist for these terms.
Signed-off-by: Markus Heiser <markus.heiser@darmarit.de>