is-promise
    isPromise(obj)
  
  Determines if object is a Promise.
var isPromise = require("can-util/js/is-promise/is-promise");
var promise = new Promise(function(resolve){
  resolve();
});
console.log(isPromise(promise)); // -> true
console.log(isPromise("foo bar")); // -> false
  
  Parameters
- obj 
{Object}:An object to be tested.
 
Returns
 {Boolean}: 
True if the object is a Promise.