#154996 by lyricnz; smarter inclusion of .js file (for memcache stats) and registering of shutdown function.

moving drupal_add_js to the shutdown function gets rid of the bootstrap problem for anonymous users when page caching is turned on.

adding hook perm, an 'access memcache statistics' permission, and using that to determine whether to show the stats.

"If you need to define global variables, their name should start with a single underscore followed by the module/theme name and another underscore"

Improving devel stats and handling the cache_set case where the expiration time is a timestamp in the future.

#134174 by lyricnz and robertDouglass: add get/set/hit statistics to the bottom of pages like devel module does with queries. Note that this marks the beginning of the rebuilding of memcache.module. All other functionality has been stripped for the time being.

Adding memcache.module (not useful until I provide patches for specific caching targets, though). Rewrote the server cluster management code in dmemcache_object. Added some (sloppily coded) tests.