Update release notes
Update release notes

eamonwoortman/RestSharp.Unity,lydonchandra/RestSharp,periface/RestSharp,rivy/RestSharp,wparad/RestSharp,PKRoma/RestSharp,Haacked/RestSharp,KraigM/RestSharp,Haacked/RestSharp,chengxiaole/RestSharp,jiangzm/RestSharp,uQr/RestSharp,haithemaraissia/RestSharp,RestSharp-resurrected/RestSharp,restsharp/RestSharp,IsCoolEntertainment/unity-restsharp,devinrader/RestSharpRTExperimental,rucila/RestSharp,mwereda/RestSharp,huoxudong125/RestSharp,felipegtx/RestSharp,wparad/RestSharp,IsCoolEntertainment/unity-restsharp,paulcbetts/RestSharp,mattwalden/RestSharp,paulcbetts/RestSharp,SaltyDH/RestSharp,cnascimento/RestSharp,kouweizhong/RestSharp,benfo/RestSharp,devinrader/RestSharpRTExperimental,dgreenbean/RestSharp,mattleibow/RestSharp,amccarter/RestSharp,fmmendo/RestSharp,who/RestSharp,dmgandini/RestSharp,dyh333/RestSharp