chore, kick clang from CI build matrix again, they don't provide nested functions

Signed-off-by: Sebastian Freundt <freundt@ga-group.nl>
Merge branch 'bld/ci'

* bld/ci:
  chore, kick clang from CI build matrix again, they don't provide nested functions
doc, update README.md, put rationale first

Signed-off-by: Sebastian Freundt <freundt@ga-group.nl>