VMM/password: Added support Blowfish/SHA-256/SHA-512 crypt().
Also updated Config and man section 5.
Config
   cfs - configset sect.opt val
   cfg - configget sect.opt
   ds - domainservices: smtp pop imap sieve???
subcommand for displaying support crypt algorithms.
- Aliases
    - avoid looping aliases
- Domain
    - optional limits for number of:
        + accounts
        + aliases
        + destinations/alias
        + alias domains
Database:
   public.users.passwd: increase to "character varying(250)"
   	why? len(VirtualMailManager.password.pwhash('1', 'crypt.hex')) -> 249
	     if VirtualMailManager.password.CRYPT_SHA512 is True and
	     misc.crypt_sha512_rounds > 0
   public.users.digestmd5: add "character varying(48)"
	Outlook will love it. (`doveadm pw -s DIGEST-MD5.hex -p 1 -u 0`)