- Patch #651240 by fago, sun: allow modules to react to changes to an entity.

includes/common.inc

includes/entity.inc

includes/file.inc

modules/comment/comment.module

modules/node/node.admin.inc

modules/node/node.module

modules/node/node.test

modules/node/tests/node_test.module

modules/simpletest/drupal_web_test_case.php

modules/simpletest/tests/file.test

modules/taxonomy/taxonomy.module

modules/user/user.module