Feature : Text align in the Notification(issue #178)

Added an option to align the text in the notification, added feature based on issue #178 .
 var n = noty({
            textAlign : 'right',      // (/right/left/center)
            text        : layout,
            type        : 'alert',
            dismissQueue: true,
            layout      : layout,
            theme       : 'defaultTheme'
        });

The value of textAlign can be (/right/left/center), if textAlign  is not used, it takes the default value.