agent: elevate unit state log level
agent: elevate unit state log level

Fix #585

ecnahc515/fleet,mischief/fleet,mwitkow/fleet,dongsupark/fleet,hhoover/fleet,bcwaldon/fleet,jonboulle/fleet,mwitkow-io/fleet,coreos/fleet,ecnahc515/fleet,wuqixuan/fleet,wuqixuan/fleet,bviswana101/fleet,mwhooker/fleet,jonboulle/fleet,mwitkow/fleet,bcwaldon/fleet,dongsupark/fleet,coreos/fleet,WPMedia/fleet,flandr/fleet,improbable-io/fleet,bviswana101/fleet,webwlsong/fleet,thepwagner/fleet,mookjp/fleet,ecnahc515/fleet,endocode/fleet,mookjp/fleet,mwitkow-io/fleet,thepwagner/fleet,dalbani/fleet,improbable-io/fleet,dalbani/fleet,bcwaldon/fleet,mwhooker/fleet,hhoover/fleet,jonboulle/fleet,mischief/fleet,endocode/fleet,giantswarm/fleet,flandr/fleet,improbable-io/fleet,dongsupark/fleet,paveltiunov/fleet,paveltiunov/fleet,dalbani/fleet,coreos/fleet,octoblu/fleet,esatterwhite/fleet,giantswarm/fleet,WPMedia/fleet,giantswarm/fleet,webwlsong/fleet,octoblu/fleet,endocode/fleet,esatterwhite/fleet