Merge user accounts

This script will merge two Moodle user accounts, “user A” and “user B”.
The intent of the script is to assign all activity & records from user A to
user B. This will give the effect of user B seeming to have done everything
both users have ever done in Moodle.
All administrators who installed this plugin are kindly invited to replace it by this:  https://moodle.org/plugins/view.php?plugin=tool_mergeusers , since the report_mergeusers plugin is no longer maintained.
In addition, there is a lot of new functionality (CLI scripts, merging reports stored in database, etc See the included README.txt for more details).