add a function to remove a user (for now he is not really removed from database but he loses every permission)
Do not give any View permission to admin account (id 1). This account should only be used to initialize the database (connecting through geneious) and to manage users and permissions (via these command line scripts)
implement changing user's password and warn about giving unencrypted passwords
use a function listall(..) to output state of database
When user is given some permission on a group, the previous permission he may had on the same group must be removed
removeuser is actually only locking user out, so we rename it
minor changes in presentation of changes to the user to make this function more generic