Fix errors in source code for stcikem

types/jquery.stickem/index.d.ts

@@ -40,12 +40,12 @@ interface StickemSettings {
     /**
      * Callback to execute when in stick state
      */
-    onStick?: Function,
+    onStick?: () => void;
 
     /**
      * Callback to execute when getting out of stick state
      */
-    onUnstick?: Function
+    onUnstick?: () => void;
 }
 
 interface JQuery {

types/jquery.stickem/jquery.stickem-tests.ts

@@ -16,4 +16,4 @@ jQuery('div').stickem({
     container: '.stickem-container',
     stickClass: 'stickit',
     endStickClass: 'stickit-end'
-});
+});