fix log persistency and add spool access for r/w

* Fix the correct mapping for /var/log - it should be reasonable in a
  non-volatile location to detect at least most startup issues
* Map /var/spool to r/w location, too - choose non-volatile one to
  allow mail sppol and at jobs survive e.g. power outage
take care weird r/w requirements of Z-Way-ware
put HP startup script to RC5, not S