* Move PKA field from models node to host level
* Move PKA field from api models node to host level
* Adapt logic package to node->host PKA
* Adapt migration-related code to node->host PKA
* Adapt cli code to node->host PKA
* Change host PKA default to 20s
* On IfaceDelta, check for PKA on host
* On handleHostRegister, set default PKA
* Use a default PKA
* Use int64 for api host pka
* Reorder imports
* Don't use host pka in iface delta
* Fix ConvertAPIHostToNMHost
* Add swagger doc for host PKA field
* Fix swagger.yml
* Set default PKA only for new hosts
* Remove TODO comment
* Remove redundant check
* Have api-host pka be specified in seconds
* remove related fields and code
* remover metrics collection from server code
* fw update struct
* add ext client flag to metrics data
* simply nat types
* rm proxy update from cli