WIP 8.x porting: doxygen doc in help, settings moved below taxonomy settings.
- info file is now in YAML.
- doxyfile mostly good.
- hook_help() integrated with doxygen doc.
- Taxonews moved from module to its own file.
- settings url moved below taxonomy
#992430, #992460, #992434, #992442, #992462 by fgm: multiple low-impact features and bugs
BUG #992430: Incorrect feed links
BUG #992460: Taxonews blocks should not be available by default on admin pages
FEAT #992434: Feed titles should be more descriptive
FEAT #992442: Feed should be added at the page level
DOC #992462: Variables available in the taxonews template are not documented