Disable memcache completely

We've determined that getting correctness semantics right, even
in the few cases that it is possible to do so (see linked bug for
audit) is not worth the bother in terms of highly complicated code
and potential bugs. This CL turns off memcache at the Ofy level
but doesn't rip out the annotations etc. so that we can quickly
turn it back on if this turns out to have been a mistake.

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=155227761

java/google/registry/model/ofy/Ofy.java

@@ -140,8 +140,7 @@ public class Ofy {
    * worth the extra complexity of reasoning about caching.
    */
   public Loader load() {
-    // TODO(b/27424173): change to false when memcache audit changes are implemented.
-    return ofy().cache(true).load();
+    return ofy().cache(false).load();
   }
 
   /**
@@ -154,7 +153,8 @@ public class Ofy {
    * worth the extra complexity of reasoning about caching.
    */
   public Loader loadWithMemcache() {
-    return ofy().cache(true).load();
+    // TODO(b/27424173): Remove this method if we determine we are ok with no memcache.
+    return ofy().cache(false).load();
   }
 
   /**