VMM/VMM: allow configure subcommand also with missing settings.
Removed method VirtualMailManager.setupIsDone()
VMM/Config: Config.load() added 'finally' clause.
Config
   cfs - configset sect.opt val
   cfg - configget sect.opt
   ds - domainservices: smtp pop imap sieve???
- Aliases
    - avoid looping aliases
- Domain
    - optional limits for number of:
        + accounts
        + aliases
        + destinations/alias
        + alias domains