fix #64

The fix handles multiple vlans across group scenario. The function
deploy_group has been broken into two function where the helper
function configures switch based on individual vlan ids.
  fix#64

  Refactored the code for deploy_group function.
  Implemented two more helper functions.
  fix#64

  Refactored code to cleanup code - removed extra function.
  Also cleaned up the doc strings.
Merge pull request #77 from abhi10/bug-64

Bug #64