User manager rewritten

Now it's two and a half year since the last refactoring of HeidiSQL's dialog for editing user accounts. The current dialog was ok from a usability point of view, but it did not allow users to assign routine privileges on newer servers. And it edited and created users by updating the tables in the mysql db directly, which is error prone, complex and not recommended by MySQL.

The new dialog now does all updates by GRANT, REVOKE, RENAME USER and SET PASSWORD, as recommended by MySQL. The GUI has also evolved:
- you can clone users now
- the entered password must be repeated
- privilege names are painted in different colors for read, write and admin relevance
But see yourself:



To get it, just go to Help > Check for updates and install the latest build.