VIRTUAL_VACATION/INSTALL.TXT:
- change instructions to use /usr/lib/postfixadmin to avoid vacation.pl
  has write access to itsself
- replace instructions for /var/spool/vacation/ with instructions for a
  log file or directory
- various other changes


git-svn-id: svn://svn.code.sf.net/p/postfixadmin/code/trunk@1692 a1433add-5e2c-0410-b055-b7f2511e0802
MailboxHandler.php:
- storemore(): 
  - fix undefined variable if creating subfolders fails (bug#328)
  - remove some outdated TODO notes
- create_mailbox_subfolders(): add $this->id to error_log


git-svn-id: svn://svn.code.sf.net/p/postfixadmin/code/trunk@1693 a1433add-5e2c-0410-b055-b7f2511e0802