• Add all new APIs upto libvirt 0.6.4 (network interfaces,
  storage volume cloning and node device create/delete)
  
• Fix off-by-1 in UUID stringification
  
• Set default values for optional params.
  
• Use SvOK check for potentially undefined string params
  
• Export all the virError related constants
  
• Fix some memory leaks in C layer
  
• Remove bogus module imports from test suite