packer: Add a script to check if all images are present on shacache

packer/util/testupload.sh

+for i in `cat SHA512SUM.txt | cut -f1 -d\ `; 
+  do 
+    python util/testurl.py http://download.shacache.org/$i && echo OK $i || echo FAIL $i 
+    sleep 10
+done

packer/util/testurl.py

+
+import urllib2
+import sys
+
+start = urllib2.urlopen(sys.argv[1]).read(24)
+
+