Detail Promises/A+ compliance
Detail Promises/A+ compliance

Closes #7

pgherveou/PromiseKit,mxcl/PromiseKit,allen-zeng/PromiseKit,allen-zeng/PromiseKit,pgherveou/PromiseKit,mxcl/PromiseKit,mxcl/PromiseKit,pgherveou/PromiseKit