Translation popup: compatibility with entity cache

Motivation

Translation popup module doesn't wokr with entitycache modules. Seems like hook_entity_load isn't invoked when entiticache is enabled.

Possible solution

Implement hook hook_entitycache_load http://cgit.drupalcode.org/entitycache/tree/entitycache.api.php#n15 which will call smartling_translate_page_popup_entity_load($entities, $type).