Simplify then. Remove experimental label from when.promise. Add jsdoc
Simplify then. Remove experimental label from when.promise. Add jsdoc

tkirda/when,SourcePointUSA/when,anthonyvia/when,stevage/when,frank-weindel/when,frank-weindel/when,ning-github/when,petkaantonov/when,caporta/when,anthonyvia/when,stevage/when,caporta/when,tkirda/when,DJDNS/when.js,mlennon3/when,mlennon3/when,ning-github/when,SourcePointUSA/when