Deprecate SLRequest `+promise:`
Deprecate SLRequest `+promise:`

If we are going to be Object Orientated, then let’s act object-orientated.

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