Can't use Leverage Browser Caching (PageSpeed ​​Insights)

I am managing external javascript in my page below

    <script async defer src="https://apis.google.com/js/platform.js?publisherid=100802427533778671877"/></script
    <script async src="//s7.addthis.com/js/300/addthis_widget.js#pubid=ra-5439942003ee228c"/></script>
    <script async src="//assets.pinterest.com/js/pinit.js"/></script>                                   
    <script src="http://platform.linkedin.com/in.js"/></script>
    <script src="/scripts/common/social.js"/></script>  

      

        
        
        
      

    

Here's the PageSpeed ​​Insights reports :

Setting an expiration date or maximum age in the HTTP headers for static resources instructs the browser to download previously downloaded resources from the local disk rather than over the network.

Use browser caching for the following caching resources:

http://assets.pinterest.com/js/pinit_main.js (5 minutes)
https://raw.githubusercontent.com/…v/www/scripts/tools/mobile-detect.min.js (5 minutes)
http://modernizr.com/downloads/modernizr-latest.js (10 minutes)
http://widgets.pinterest.com/…callback=PIN_1414678084159.f.callback[0] (14.8 minutes)
http://cdn.syndication.twitter.com/…ophyips.info&callback=twttr.receiveCount (15 minutes)
http://connect.facebook.net/en_US/sdk.js (20 minutes)
https://apis.google.com/js/api.js (30 minutes)
https://apis.google.com/…orm.js?publisherid=100802427533778671877 (30 minutes)
https://oauth.googleusercontent.com/…e:rpc:shindig.random:shindig.sha1.js?c=2 (60 minutes)
http://www.google-analytics.com/analytics.js (2 hours)
http://platform.linkedin.com/in.js (4.8 hours)

      

        
        
        
      

    

How can I pass this when running these scripts in Google Appeengine (can't install Apache httpd.conf).