Hi,

it would be nice to have as an admin the ability to change the usernames of the piwik user.

My suggestion on how to proceed :
First step: Add a user ident to the "piwik_user" table.
Second step: Change all user relations in the datebase in the upgrade process to this new ident.
Third step: Make the username editable through the piwk backend for all user with the "superuser_access" flag.

Thanks for the great software and best regards
Schwindelbub