Data Model: Align with new reference APIs

See merge request !3

Mohd Mehdi authored 10 months ago and Rahul Thakur committed 10 months ago

* functions, macros and structs related to DHCP are added from
  dmcommon to dhcpmngr, but not removed from bbfdm yet
* slight renaming is done (dhcpmngr prefixed) to avoid name
  clash

* add support for DHCP data model objects as micro service (moved
  from bbfdm)
* add udhcpc.user.d script to keep track of remaining lease time
  (moved from bbfdm)
* replace function calls that do not work in micro service mode
* add pipeline