Some things TODO

[YouDirk]

• Test Doxygen generate_treeview
• Test Doxygen if @home warnings are filtered
• Doxygen set generate_man
• Rename src/libathome-common/libathome-*{,.templ}.hpp
• Make implicite version check, if Header-Files using the same version as shared linked library
• Begin Filesystem:: and Log-Rotation stuff
• Update GitHub Sponsors page (remove Patreon link?)
• Make Credits section in README.md (make Todo Issue --credits)
• Create CONTRIBUTING.md, includes Sponsoring as kind of contirbution
• Link Sponsors page in README.md, CONTRIBUTING.md
• Add https://youdirk.github.io/libathome-doc/ to Google search index
• @ref All Doxygen refernces to enforce warnings if something brokes