0.23.1
make dist: Fix HFILE_GLOB in docs/libpsl/Makefile.am
gtk-doc: do not include tree_index.sgml
Add PSL_API to libpsl-sections.txt
fixed docs for 'make distcheck' after 'make clean'
meson: also rename cdata to _cdata in docs/libpsl/meson.build
remove LIBPSL_API_VERSION for simplicity