How to install
1. Include the following files before body tag close.
            <link href="path_to/jcalculator.css" rel="stylesheet" type="text/css">
            <-- jQuery library -->
            <script type="text/javascript" src="path_to/jquery.js"></script>
            <script type="text/javascript" src="path_to/jcalculator.min.js"></script>
        
2. Call the jCalculator plugin.
            <script type="text/javascript"> 
            $('#yourInput').calculator();
        
            </script>