feat(validate): Added support for promises
feat(validate): Added support for promises

Merged from angular-ui/angular-ui#426

sndp-vrma/ui-utils,behzad88/ui-utils,pedroso/ui-mask,zhaokunfay/ui-indeterminate,RafaelTaranto/ui-mask,r0b-/ui-validate,xuwupeng2000/ui-event,zhaokunfay/ui-uploader,graingert/ui-jq,zhaokunfay/ui-mask,zhaokunfay/ui-event,NickTomlin/ui-mask,zhaokunfay/ui-scrollpoint,angular-ui/ui-indeterminate,angular-ui/ui-utils,graingert/ui-keypress,marbletravis/ui-mask,marbletravis/ui-mask,aniellepizzo/ui-scrollpoint,NickTomlin/ui-mask,zhaokunfay/ui-validate,zhaokunfay/ui-indeterminate,akhilshastri/ui-utils,aniellepizzo/ui-scrollpoint,zhaokunfay/ui-scrollpoint,mengshadow/angularjs,angular-ui/ui-mask,lukepfeiffer10/ui-mask,angular-ui/ui-validate,RafaelTaranto/ui-mask,zhaokunfay/ui-uploader,angular-ui/ui-scrollpoint,Queatz/ui-validate,saike/ui-mask,angular-ui/ui-uploader,angular-ui/ui-scrollpoint,pedroso/ui-mask,lith-light-g/ui-scrollpoint,DexStr/ui-uploader,graingert/ui-keypress,angular-ui/ui-event,modulexcite/ui-utils,DexStr/ui-uploader,sndp-vrma/ui-utils,zhaokunfay/ui-event,lukepfeiffer10/ui-mask,isaacplmann/ui-mask,angular-ui/ui-event,xml/ui-mask,xml/ui-mask,graingert/ui-utils,isaacplmann/ui-mask,gdi2290/ui-utils,angular-ui/ui-indeterminate,r0b-/ui-validate,Mojility/ui-uploader,zhaokunfay/ui-validate,lu4/ui-mask,zhaokunfay/ui-mask,lith-light-g/ui-scrollpoint,Mojility/ui-uploader,HawkHouseIntegration/ui-mask,graingert/ui-jq,lu4/ui-mask,KingMario/ui-uploader,graingert/ui-utils,xuwupeng2000/ui-event,saike/ui-mask,KingMario/ui-uploader,mengshadow/angularjs,Queatz/ui-validate,HawkHouseIntegration/ui-mask