[release] prepare for release auto-value-1.0-rc4
[release] prepare for release auto-value-1.0-rc4

wuqiangxjtu/auto,eamonnmcmanus/auto,MaTriXy/auto,THEONE10211024/auto,adriancole/auto,rharter/auto,Eagles2F/auto,google/auto,google/auto,tbroyer/auto,ruhaly/auto,gnanam336/auto,sitexa/auto,aglne/auto,google/auto,adriancole/auto,ruhaly/auto,sitexa/auto,wuqiangxjtu/auto,MaTriXy/auto,cgruber/auto,gnanam336/auto,agilemobiledev/auto,aglne/auto,Eagles2F/auto,eamonnmcmanus/auto,eamonnmcmanus/auto,tbroyer/auto,cgruber/auto,agilemobiledev/auto,rharter/auto,THEONE10211024/auto