- changes in MDAPI DLD - added subchapter about nested locks issue.

- added more checks in GNS stuff:

  - check for zero len mount object (mostly admin friendly thing, to show that
    mount object is formed not correctly)

  - set default GNS callback to "/usr/sbin/gns_upcall"

  - added checks in lproc stuff:
    - gns object name should be differnt than upcall
    - gns timeout should be bigger than gns tick