v0.2.0

Adds following commands

• lease commands for dhcp4
  • lease4-add
  • lease4-del
  • lease4-get
  • lease4-get-all
  • lease4-get-by-client-id
  • lease4-get-by-hostname
  • lease4-get-by-hw-address
  • lease4-resend-ddns
  • lease4-update
  • lease4-wipe
  • leases-reclaim
• subnet commands for dhcp4
  • subnet4-add
  • subnet4-del
  • subnet4-get
  • subnet4-list
  • subnet4-update
• network commands for dhcp4
  • network4-add
  • network4-del
  • network4-get
  • network4-list
  • network4-subnet-add
  • network4-subnet-add