Update designs/cache_options.md

Co-authored-by: Steven E. Harris <seh@panix.com>

designs/cache_options.md

@@ -13,7 +13,7 @@ the future.
 
 ## Non-Goals
 
-* Line out how the actual implementation of the cache itself will look like.
+* Describe the design and implementation of the cache itself.
   The assumption is that the most granular level we will end up with is
   "per-object multiple namespaces with distinct selectors" and that this
   can be implemented using a "meta cache" that delegates per object and by