add "unstable API" warning to readme
add "unstable API" warning to readme
kelsadita/kefir,pixelpicosean/kefir,AyaMorisawa/kefir,elsehow/kefir,AgentME/kefir,pixelpicosean/kefir,lautis/kefir,kelsadita/kefir,hsavit1/kefir,elsehow/kefir,AyaMorisawa/kefir,lautis/kefir,AgentME/kefir,hsavit1/kefir