Merge pull request #45 from /issues/44

Issues/44 Not working on Unity 2018.3.3f1 #44

2018-09-14: fix OnError handling, update UniRx 6.2.2

2017-10-11 filecache asynchronous

2017-05-07 create encoder/decoder

2017-01-17: fix for directory not found exception

2017-01-16 first preview release