Add users cli commands to docs
Fix checking for changing username or user email
Add user status change command
Make sure only one user exists with a particular email when updating
Add password reset
Add user id to help
Remove user delete (too many possible side effects, postponed until later)
Make sure to fail on any errors
Fail if changing the username would result in duplicate users
Add user update command
Add user create command
Add command stubs for all commands
Render users in a beautiful table
Started adding user list command
Co-authored-by: kolaente <k@knt.li>
Reviewed-on: https://kolaente.dev/vikunja/api/pulls/632
