*Really* display correct expiration date on license page.

calcDaysRemaining has recently been updated to return a string (`${duration} Days`) and calcExpiresOn was getting confused.

This change feels a little hacky but it gets the job done. I'm open to other suggestions if anyone has them.

awx/ui/client/src/license/license.controller.js

@@ -74,6 +74,7 @@ export default
 
         var calcExpiresOn = function(days){
             // calculate the expiration date of the license
+            days = parseInt(days);
             return moment().add(days, 'days').calendar();
         };
         var init = function(){