VMM/handler: Handler._get_{account,alias,relocated}() check
if the address is already in use.
.. Substitutions in section 1
.. |account.disk_usage| replace:: `account.disk_usage`
.. _account.disk_usage: vmm.cfg.5#account-disk-usage
.. |account.random_password| replace:: `account.random_password`
.. _account.random_password: vmm.cfg.5#account-random-password
.. |domain.auto_postmaster| replace:: `domain.auto_postmaster`
.. _domain.auto_postmaster: vmm.cfg.5#domain-auto-postmaster
.. |domain.force_deletion| replace:: `domain.force_deletion`
.. _domain.force_deletion: vmm.cfg.5#domain-force-deletion
.. |misc.transport| replace:: `misc.transport`
.. _misc.transport: vmm.cfg.5#misc-transport
.. #EOF