scripts:Add string-based VUID to db file

Include the new, string-based Valid Usage Unique IDs in the validation
database file. This will be use to map between the old ids and these
new ids.

These script updates are a bit hacky as the migration is underway and
function is being favored over form. Once migration is complete I can
strip down spec.py script to core functionality which should be much
cleaner and simpler than either the original code or this current form.
diff --git a/layers/vuid_mapping.py b/layers/vuid_mapping.py
index 96d93c6..2151264 100644
--- a/layers/vuid_mapping.py
+++ b/layers/vuid_mapping.py
@@ -913,7 +913,7 @@
     if uniqueid in uniqueid_set:
         print ("ERROR: Uniqueid %d for string id %s is a duplicate!" % (uniqueid, vuid_string))
         print (" TODO: Figure out what caused the dupe and fix it")
-        #sys.exit()
+        sys.exit()
     print ("Storing uniqueid %d for unique string %s" % (uniqueid, vuid_string))
     uniqueid_set.add(uniqueid)
 #    if func_struct_update: