Update ajaxmask.js

Remove .ajax-mask class only from elements that were received as arguments.
eg.  
Add several masks to page:  $('#div1').ajaxMask(); $('#div2').ajaxMask(); $('.my_table').ajaxMask();
I want remove mask only from ".my_table": $('.my_table').ajaxMask({ stop:true });
Div2 and Div2 will be stay under the mask.