Fixed isPromise

Author: andot

dist/hprose.js

@@ -1778,7 +1778,7 @@
     }
 
     function isPromise(obj) {
-        return 'function' == typeof obj.then;
+        return 'function' === typeof obj.then;
     }
 
     function toPromise(obj) {

dist/hprose.min.js

@@ -58,7 +58,7 @@
     }
 
     function isPromise(obj) {
-        return 'function' == typeof obj.then;
+        return 'function' === typeof obj.then;
     }
 
     function toPromise(obj) {